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Brain Functional Network Changes in Patients with Poststroke Cognitive Impairment Following Acupuncture Therapy
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作者 Ran Wang Nian Liu +4 位作者 Hao Xu Peng Zhang Xiaohua Huang Lin Yang Xiaoming Zhang 《Health》 2024年第9期856-871,共16页
Background: The mechanisms by which acupuncture affects poststroke cognitive impairment (PSCI) remain unclear. Objective: To investigate brain functional network (BFN) changes in patients with PSCI after acupuncture t... Background: The mechanisms by which acupuncture affects poststroke cognitive impairment (PSCI) remain unclear. Objective: To investigate brain functional network (BFN) changes in patients with PSCI after acupuncture therapy. Methods: Twenty-two PSCI patients who underwent acupuncture therapy in our hospital were enrolled as research subjects. Another 14 people matched for age, sex, and education level were included in the normal control (HC) group. All the subjects underwent resting-state functional magnetic resonance imaging (rs-fMRI) scans;the PSCI patients underwent one scan before acupuncture therapy and another after. The network metric difference between PSCI patients and HCs was analyzed via the independent-sample t test, whereas the paired-sample t test was employed to analyze the network metric changes in PSCI patients before vs. after treatment. Results: Small-world network attributes were observed in both groups for sparsities between 0.1 and 0.28. Compared with the HC group, the PSCI group presented significantly lower values for the global topological properties (γ, Cp, and Eloc) of the brain;significantly greater values for the nodal attributes of betweenness centrality in the CUN. L and the HES. R, degree centrality in the SFGdor. L, PCG. L, IPL. L, and HES. R, and nodal local efficiency in the ORBsup. R, ORBsupmed. R, DCG. L, SMG. R, and TPOsup. L;and decreased degree centrality in the MFG. R, IFGoperc. R, and SOG. R. After treatment, PSCI patients presented increased degree centrality in the LING.L, LING.R, and IOG. L and nodal local efficiency in PHG. L, IOG. R, FFG. L, and the HES. L, and decreased betweenness centrality in the PCG. L and CUN. L, degree centrality in the ORBsupmed. R, and nodal local efficiency in ANG. R. Conclusion: Cognitive decline in PSCI patients may be related to BFN disorders;acupuncture therapy may modulate the topological properties of the BFNs of PSCI patients. 展开更多
关键词 Cognitive Decline Poststroke Cognitive Impairment functional Magnetic Resonance Imaging Brain functional Network Graph theoretical Analysis
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Lychrel Numbers in Base 10: A Probabilistic Approach
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作者 Rostand S. Kuitché 《Advances in Pure Mathematics》 2024年第8期667-694,共28页
For decades, Lychrel numbers have been studied on many bases. Their existence has been proven in base 2, 11 or 17. This paper presents a probabilistic proof of the existence of Lychrel number in base 10 and provides s... For decades, Lychrel numbers have been studied on many bases. Their existence has been proven in base 2, 11 or 17. This paper presents a probabilistic proof of the existence of Lychrel number in base 10 and provides some properties which enable a mathematical extraction of new Lychrel numbers from existing ones. This probabilistic approach has the advantage of being extendable to other bases. The results show that palindromes can also be Lychrel numbers. 展开更多
关键词 Probabilistic Approach PALINDROMES Lychrel numbers Iteration function DIGITS
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Properties of Some Kind of Number Theoretical Function(Ⅱ)
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作者 李怡君 刘华柯 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第3期402-405,共4页
For any given positive integer n ≥ 1, the Euler function φ(n) is defined to be the number of positive integers not exceeding n, which is relatively prime to n. o:(n) is defined to be the number of different pri... For any given positive integer n ≥ 1, the Euler function φ(n) is defined to be the number of positive integers not exceeding n, which is relatively prime to n. o:(n) is defined to be the number of different prime divisors of n. In order to know the solvability of the function of φ(φ(φ(n))) = 2^ω(n), properties of the number theoretical function φ(φ(n)) is studied in the paper. 展开更多
关键词 Euler function SOLUTIONS number of solutions divide exactly
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Physical Properties of the Function and Number of Empirical Macrohardness of the Material: Universal Physical Unit of Measurement of Macro Hardness (Part 2)
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作者 Shtyrov Nikolay 《Journal of Mechanics Engineering and Automation》 2023年第3期79-91,共13页
Results of analytical studies of the physical properties of the function and number of empirical macrohardness based on the standard experimental force diagram of kinetic macroindentation by a sphere.An analytical com... Results of analytical studies of the physical properties of the function and number of empirical macrohardness based on the standard experimental force diagram of kinetic macroindentation by a sphere.An analytical comparison method and a criterion for the similarity of the physical and empirical macrohardness of a material are proposed.The physical properties of the hardness measurement process using the Calvert-Johnson method are shown.The physical reasons for the size effect when measuring macrohardness are considered.The universal physical unit and standard of macrohardness of kinetic macroindentation by a sphere is substantiated. 展开更多
关键词 Physical theory of kinetic indentation method for determining the function and number of physical macrohardness ratio of empirical and physical macrohardness of a material universal physical unit of macrohardness.
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Dynamic Analysis of Customer Demand Based on Intuitionistic Fuzzy Number in Product Planning
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作者 Yongguang Yi Zengqiang Wang 《Proceedings of Business and Economic Studies》 2024年第5期127-131,共5页
To address the fuzziness and variability in determining customer demand importance,a dynamic analysis method based on intuitionistic fuzzy numbers is proposed.First,selected customers use intuitionistic fuzzy numbers ... To address the fuzziness and variability in determining customer demand importance,a dynamic analysis method based on intuitionistic fuzzy numbers is proposed.First,selected customers use intuitionistic fuzzy numbers to represent the importance of each demand.Then,the preference information is aggregated using customer weights and time period weights through the intuitionistic fuzzy ordered weighted average operator,yielding a dynamic vector of the subjective importance of the demand index.Finally,the feasibility of the proposed method is demonstrated through an application example of a vibrating sorting screen. 展开更多
关键词 Quality function deployment Customer demand Intuitionistic fuzzy number Dynamic analysis method
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A Number Theoretic Function and Its Mean Value Computation 被引量:1
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作者 李海龙 杨倩丽 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期53-56,共4页
Let p be a prime, n be any positiv e integer, α(n,p) denotes the power of p in the factorization of n! . In this paper, we give an exact computing formula of the mean value ∑ n<Nα(n,p).
关键词 number theoretic function mean value computing formula
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Fuzzy Semi-continuity of fuzzy number-valued function 被引量:3
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作者 Magassy OUS MANE 吴从炘 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期139-141,共3页
In this paper we discuss the conecept and property of fuzzy semi continuous function.
关键词 FUZZY numberS FUZZY number-valued function FUZZY SEMI-CONTINUOUS function
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Ideal Statistically Pre-Cauchy Triple Sequences of Fuzzy Number and Orlicz Functions 被引量:1
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作者 Xue Feng 《Applied Mathematics》 2021年第9期767-774,共8页
In this paper, we extend the notions of ideal statistically convergence for sequence of fuzzy number. We introduce the notions ideal statistically pre-Cauchy triple sequences of fuzzy number about Orlicz function, and... In this paper, we extend the notions of ideal statistically convergence for sequence of fuzzy number. We introduce the notions ideal statistically pre-Cauchy triple sequences of fuzzy number about Orlicz function, and give some correlation theorem. It is shown that <em>x</em> = {<em>x<sub>ijk</sub></em>} is ideal statistically pre-Cauchy if and only if <img src="Edit_0f9eaa1e-440b-4bac-8bae-c50bb5e5c244.bmp" alt="" /> <em>D </em>(<em>x<sub>ijk</sub></em>, <em>x<sub>pqr</sub></em>) ≥ <em>ε</em>, <em>i</em> ≤ <em>m</em>,<em> j </em>≤ <em>n</em>, <em>t </em>≤ <em>k</em>}| ≥ <em>δ</em>} &#8712;<em>I</em>. At the same time, we have proved <em>x</em> = {<em>x<sub>ijk</sub></em>} is ideal statistically convergent to <em>x</em><sub>0</sub> if and only if <img src="Edit_343f4dfc-82c3-4985-aebc-95c52795bb2f.bmp" alt="" />. Also, some properties of these new sequence spaces are investigated. 展开更多
关键词 Fuzzy numbers Ideal Statistical Convergence Orlicz functions
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Special Numbers on Analytic Functions
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作者 Yilmaz Simsek 《Applied Mathematics》 2014年第7期1091-1098,共8页
The aim of this paper is to give some analytic functions which are related to the generating functions for the central factorial numbers. By using these functions and p-adic Volkenborn integral, we derive many new ide... The aim of this paper is to give some analytic functions which are related to the generating functions for the central factorial numbers. By using these functions and p-adic Volkenborn integral, we derive many new identities associated with the Bernoulli and Euler numbers, the central factorial numbers and the Stirling numbers. We also give some remarks and comments on these analytic functions, which are related to the generating functions for the special numbers. 展开更多
关键词 BERNOULLI numberS Euler numberS The Central FACTORIAL numberS Array Polynomials STIRLING numberS of the First KIND and the Second KIND Generating function functional Equation Analytic functions
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Quantum phase distribution and the number-phase Wigner function of the generalized squeezed vacuum states associated with solvable quantum systems
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作者 G.R.Honarasa M.K.Tavassoly M.Hatami 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期265-273,共9页
The quantum phase properties of the generalized squeezed vacuum states associated with solvable quantum systems are studied by using the Pegg-Barnett formalism.Then,two nonclassical features,i.e.,squeezing in the numb... The quantum phase properties of the generalized squeezed vacuum states associated with solvable quantum systems are studied by using the Pegg-Barnett formalism.Then,two nonclassical features,i.e.,squeezing in the number and phase operators,as well as the number-phase Wigner function of the generalized squeezed states are investigated.Due to some actual physical situations,the present approach is applied to two classes of generalized squeezed states:solvable quantum systems with discrete spectra and nonlinear squeezed states with particular nonlinear functions.Finally,the time evolution of the nonclassical properties of the considered systems has been numerically investigated. 展开更多
关键词 squeezed vacuum states solvable quantum systems phase distribution number phaseWigner function
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IS THE“DEGREE OF AGGREGATION”A FUNCTION OF THE AVERAGE AGGREGATE NUMBER,OR OF THE NUMBER OF AGGREGATES,OR BOTH?
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作者 Xi Kui JIANG Jin Tao ZHANG Shanghai Institute of Organic Chemistry,Academia Sinica,345 Ling-ling LU,Shanghai 200032 Zhen He TONG Laboratory of Photochemistry,Institute of Photographic Chemistry,Academia Sinica,Beijing 100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第9期675-676,共2页
Measurement of the average aggregate number of coaggregates(N_co)and evaluation Of the number of coaggregates([CoAg])in the region of increasing degree of aggregation shows that only N_co increases linearly with the c... Measurement of the average aggregate number of coaggregates(N_co)and evaluation Of the number of coaggregates([CoAg])in the region of increasing degree of aggregation shows that only N_co increases linearly with the concentration of the target molecules CE-In and BL-ol. 展开更多
关键词 Menger A function OF THE AVERAGE AGGREGATE number OR OF THE number OF AGGREGATES OR BOTH DEGREE OF AGGREGATION IS THE Figure OC
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Corresponding Prime Number Distribution Equation 被引量:1
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作者 Dan Liu Chenglong Liu 《Journal of Applied Mathematics and Physics》 2023年第11期3354-3365,共12页
The conjecture of twin prime numbers is a mathematical problem. Proving the twin prime conjecture using traditional modern number theory is extremely profound and complex. We propose an elementary research method for ... The conjecture of twin prime numbers is a mathematical problem. Proving the twin prime conjecture using traditional modern number theory is extremely profound and complex. We propose an elementary research method for corresponding prime number, proved that the conjecture of twin prime numbers and obtain the corresponding prime distribution equation. According to the distribution rate of corresponding prime numbers, the distribution pattern of twin prime numbers was proved the distribution rate theorem. This is the distribution rate of prime numbers corresponding to composite numbers, which approaches the distribution rate of prime numbers corresponding to integers. Based on the corresponding prime distribution equation, obtain the twin prime inequality function. Then, the formula for calculating twin prime numbers was discussed. There is also the Hardy Littlewood conjecture. This provides a practical and feasible approach for studying the distribution of twin prime numbers. 展开更多
关键词 Prime number Composite number Twin Prime numbers Corresponding Prime Distribution Equation Twin Prime Inequality function
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Travelling Waves: Interplay of Low to High Reynolds Number and Tan-Cot Function Method to Solve Burger’s Equations
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作者 Md. Kamrujjaman Asif Ahmed Jahrul Alam 《Journal of Applied Mathematics and Physics》 2019年第4期861-873,共13页
We study the nonlinear parabolic equations for travelling wave solutions of Burger’s equations. The purpose of the present work is to study various types of Burger’s equations describing waves and those are based on... We study the nonlinear parabolic equations for travelling wave solutions of Burger’s equations. The purpose of the present work is to study various types of Burger’s equations describing waves and those are based on nonlinear equations. We focus on to describe the analytic solution in the special pattern of travelling wave solutions using tan-cot function method. We discuss about inviscid and viscous version of Burger’s equation for fluid flow and investigate the effects of internal friction of a fluid via Reynolds number. By changing the velocity amplitude, the nature of flows with shock wave and disturbance are observed. For numerical solutions, the Crank-Nicolson scheme is introduced to establish the wave solutions. 展开更多
关键词 Nonlinear PDES Tan-Cot function Method TRAVELLING Wave Solutions Burg-er’s Equation REYNOLDS number CRANK-NICOLSON Scheme
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On AP-Henstock Integrals of Interval-Valued Functions and Fuzzy-Number-Valued Functions
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作者 Muawya Elsheikh Hamid Alshaikh Hamed Elmuiz Mohammed Eldirdiri Sheima 《Applied Mathematics》 2016年第18期2285-2295,共11页
In 2000, Wu and Gong [1] introduced the thought of the Henstock integrals of inter-valvalued functions and fuzzy-number-valued functions and obtained a number of their properties. The aim of this paper is to introduce... In 2000, Wu and Gong [1] introduced the thought of the Henstock integrals of inter-valvalued functions and fuzzy-number-valued functions and obtained a number of their properties. The aim of this paper is to introduce the thought of the AP- Henstock integrals of interval-valued functions and fuzzy-number-valued functions which are extensions of [1] and investigate a number of their properties. 展开更多
关键词 Fuzzy numbers AP-Henstock Integrals of Interval-Valued functions AP-Henstock Integrals of Fuzzy-number-Valued functions
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Describing Fuzzy Membership Function and Detecting the Outlier by Using Five Number Summary of Data
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作者 Md. Farooq Hasan Md. Abdus Sobhan 《American Journal of Computational Mathematics》 2020年第3期410-424,共15页
One of the most important activities in data science is defining a membership function in fuzzy system. Although there are few ways to describe membership function like artificial neural networks, genetic algorithms e... One of the most important activities in data science is defining a membership function in fuzzy system. Although there are few ways to describe membership function like artificial neural networks, genetic algorithms etc.;they are very complex and time consuming. On the other hand, the presence of outlier in a data set produces deceptive results in the modeling. So it is important to detect and eliminate them to prevent their negative effect on the modeling. This paper describes a new and simple way of constructing fuzzy membership function by using five-number summary of a data set. Five states membership function can be created in this new method. At the same time, if there is any outlier in the data set, it can be detected with the help of this method. Usually box plot is used to identify the outliers of a data set. So along with the new approach, the box plot has also been drawn so that it is understood that the results obtained in the new method are accurate. Several real life examples and their analysis have been discussed with graph to demonstrate the potential of the proposed method. The results obtained show that the proposed method has given good results. In the case of outlier, the proposed method and the box plot method have shown similar results. Primary advantage of this new procedure is that it is not as expensive as neural networks, and genetic algorithms. 展开更多
关键词 Fuzzy Set Membership function Five number Summary OUTLIERS
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On Henstock-Stieltjes Integrals of Interval-Valued Functions and Fuzzy-Number-Valued Functions
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作者 Muawya Elsheikh Hamid Alshaikh Hamed Elmuiz 《Journal of Applied Mathematics and Physics》 2016年第4期779-786,共8页
In this paper we introduce the notion of the Henstock-Stieltjes (HS) integrals of interval-valued functions and fuzzy-number-valued functions and discuss some of their properties.
关键词 Fuzzy numbers Henstock-Stieltjes (HS) Integrals of Interval-Valued functions Henstock-Stieltjes (HS) Integrals of Fuzzy-number-Valued functions
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基于GBM算子的不平衡概率语言Z-number多属性群决策
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作者 陈向 张晓珍 +1 位作者 刘嘉俊 毛军军 《高师理科学刊》 2023年第3期14-20,共7页
Z-number作为一种有效的信息表达方式,能够很好的描述带有不确定信息的自然语言.但大多数关于Z-number的研究依赖于均匀分布的语言术语集,并且用于聚合Z-number信息的聚合算子很少能够考虑属性之间的关系.提出一种非均匀分布的语言尺度... Z-number作为一种有效的信息表达方式,能够很好的描述带有不确定信息的自然语言.但大多数关于Z-number的研究依赖于均匀分布的语言术语集,并且用于聚合Z-number信息的聚合算子很少能够考虑属性之间的关系.提出一种非均匀分布的语言尺度函数,讨论了概率语言Z-number在不平衡语义下的情形,运用定义的新型算子对于概率语言Z-number进行聚合.定义相关运算以及得分函数,构建多目标线性优化模型确定最佳投资比例.通过实例说明了所提出方法的可行性与有效性,并进行了灵敏度分析. 展开更多
关键词 多属性群决策 Z-number Bonferroni几何平均算子 得分函数
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基于非负矩阵分解的函数型聚类算法改进与比较
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作者 王丙参 魏艳华 李旭 《统计与决策》 CSSCI 北大核心 2024年第15期46-52,共7页
非负函数型数据可以不等间隔观测,在理论和实践中应用广泛,对其进行聚类可以更好地探索客观规律。文章利用位置积分变换将函数型数据转化为高维向量,再通过非负矩阵分解(NMF)将其转化为低维向量,以此构建函数型聚类算法。针对基于NMF的... 非负函数型数据可以不等间隔观测,在理论和实践中应用广泛,对其进行聚类可以更好地探索客观规律。文章利用位置积分变换将函数型数据转化为高维向量,再通过非负矩阵分解(NMF)将其转化为低维向量,以此构建函数型聚类算法。针对基于NMF的函数型谱聚类算法,给出了确定聚类个数K的两种方法:一种是根据Laplacian矩阵的特征值确定K;另一种是构建新评价指标,通过搜索确定K。数值实验结果显示:基于位置积分变换和NMF的函数型聚类算法有效,对函数结构要求宽松,但需限制函数取值为正;NMF的秩可通过cophenetic相关系数确定,建议取较小的值,以剔除类的冗余特征。在确定谱聚类的聚类个数K时,建议对降维后的数据进行标准化处理,以缩小样本间的距离变化范围;聚类个数变点图直观有效,再结合特征值差分法确定K很有参考价值,建议阈值取[0.05,0.08];根据吻合度与相似比确定K的方法有效且简单易懂。 展开更多
关键词 函数型数据 非负矩阵分解 谱聚类 聚类个数
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熔融温度对DLC薄膜杂化状态影响的分子动力学研究
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作者 罗宏博 杨来东 +2 位作者 连潇 王建吉 朱砚 《真空科学与技术学报》 CAS CSCD 北大核心 2024年第3期266-271,共6页
文章基于Tersoff势函数,采用分子动力学方法建立金刚石的分子模型,分析了不同熔融温度和冷却过程对原子键合结构,径向分布函数曲线和配位数的影响,从原子尺度阐明了DLC薄膜制备过程中原子形态杂化的形成机理。研究发现:DLC薄膜主要由C-... 文章基于Tersoff势函数,采用分子动力学方法建立金刚石的分子模型,分析了不同熔融温度和冷却过程对原子键合结构,径向分布函数曲线和配位数的影响,从原子尺度阐明了DLC薄膜制备过程中原子形态杂化的形成机理。研究发现:DLC薄膜主要由C-sp3和C-sp2杂化相组成,当温度低于6000 K时,熔融和冷却基本不会使C-sp3杂化发生结构转变,薄膜的性能比较稳定。当温度高于7000 K时,熔融过程中有大量的C-sp3杂化原子转变为C-sp2和C-sp1,冷却和弛豫平衡会引起高能态C-sp3杂化原子转变为C-sp2,但C-sp1杂化的含量基本不变。熔融温度主要影响DLC薄膜制备过程中C-sp3和C-sp2相的百分比含量,当体系中C-sp2含量超过40%,薄膜的性能将趋向于石墨。 展开更多
关键词 分子动力学 熔融温度 径向分布函数 配位数 类金刚石 杂化
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与调和数有关的一类极限
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作者 雷冬霞 邱小霞 黄永忠 《大学数学》 2024年第5期43-47,共5页
利用Abel分部求和公式和Newton二项式定理对极限■给出计算式子,其中H_(n)(p)=■p,m,n为非负整数,p,q均为正整数,且p>1.进而给出n=0或m=0时以及m=n=1时的几个具体算例.
关键词 调和数 极限 Abel分部求和公式 ZETA函数
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