In this paper, we discussed w-extension of bicyclic semigroups. Two types of this extension are proposed. In §2 we discussed strong semilattice extension and the structure of the extension is well presented. In &...In this paper, we discussed w-extension of bicyclic semigroups. Two types of this extension are proposed. In §2 we discussed strong semilattice extension and the structure of the extension is well presented. In §3 we discussed another order extension. We proved that congruence lattice of this extension semigroups is union set of two sublattice. One is the group congruence semilattice, the other is the pure idempotent congruence semilattice.展开更多
We prove some 3-adic congruences for binomial sums,which were conjectured by Zhi-Wei Sun.For example,for any integer m≡1(mod 3)and any positive integer n,we have v3(1/n ∑n-1X k=0 1/mk 2k/ k〉))≥min{3(n),3(...We prove some 3-adic congruences for binomial sums,which were conjectured by Zhi-Wei Sun.For example,for any integer m≡1(mod 3)and any positive integer n,we have v3(1/n ∑n-1X k=0 1/mk 2k/ k〉))≥min{3(n),3(m-1)-1},where 3(n)denotes the 3-adic order of n.In our proofs,we use several auxiliary combinatorial identities and a series converging to 0 over the 3-adic field.展开更多
Let p 〉 3 be a prime. A p-adic congruence is called a super congruence if it happens to hold modulo some higher power of p. The topic of super congruences is related to many fields including Gauss and Jacobi sums and...Let p 〉 3 be a prime. A p-adic congruence is called a super congruence if it happens to hold modulo some higher power of p. The topic of super congruences is related to many fields including Gauss and Jacobi sums and hypergeometric series. We prove that ∑k=0^p-1(k^2k/2k)≡(-1)^(p-1)/2-p^2Ep-3(modp^3) ∑k=1^(p-1)/2(k^2k)/k≡(-1)^(p+1)/2 8/3pEp-3(mod p^2),∑k=0^(p-1)/2(k^2k)^2/16k≡(-1)^(p-1)/2+p^2Ep-3(mod p^3),where E0, E1, E2,... are Euler numbers. Our new approach is of combinatorial nature. We also formulate many conjectures concerning super congruences and relate most of them to Euler numbers or Bernoulli numbers. Motivated by our investigation of super congruences, we also raise a conjecture on 7 new series for π2, π-2 and the constant K := ∑k=1^∞(k/3)/k^2 (with (-) the Jacobi symbol), two of which are ∑k=1^∞(10k-3)8k/k2(k^2k)^2(k^3k)=π^2/2and ∑k=1^∞(15k-4)(-27)^k-1/k^3(k^2k)^2(k^3k)=K.展开更多
基金Supported by the NNSF of China(6047303060773035)
文摘In this paper, we discussed w-extension of bicyclic semigroups. Two types of this extension are proposed. In §2 we discussed strong semilattice extension and the structure of the extension is well presented. In §3 we discussed another order extension. We proved that congruence lattice of this extension semigroups is union set of two sublattice. One is the group congruence semilattice, the other is the pure idempotent congruence semilattice.
基金supported by National Natural Science Foundation of China (Grant Nos. 11271185,11171140 and 11226277)the Initial Founding of Scientific Research for the Introduction of Talents of Nanjing Institute of Technology,China (Grant No. YKJ201115)
文摘We prove some 3-adic congruences for binomial sums,which were conjectured by Zhi-Wei Sun.For example,for any integer m≡1(mod 3)and any positive integer n,we have v3(1/n ∑n-1X k=0 1/mk 2k/ k〉))≥min{3(n),3(m-1)-1},where 3(n)denotes the 3-adic order of n.In our proofs,we use several auxiliary combinatorial identities and a series converging to 0 over the 3-adic field.
基金supported by the National Natural Science Foundation of China(GrantNo.10871087)the Overseas Cooperation Fund of China(Grant No.10928101)
文摘Let p 〉 3 be a prime. A p-adic congruence is called a super congruence if it happens to hold modulo some higher power of p. The topic of super congruences is related to many fields including Gauss and Jacobi sums and hypergeometric series. We prove that ∑k=0^p-1(k^2k/2k)≡(-1)^(p-1)/2-p^2Ep-3(modp^3) ∑k=1^(p-1)/2(k^2k)/k≡(-1)^(p+1)/2 8/3pEp-3(mod p^2),∑k=0^(p-1)/2(k^2k)^2/16k≡(-1)^(p-1)/2+p^2Ep-3(mod p^3),where E0, E1, E2,... are Euler numbers. Our new approach is of combinatorial nature. We also formulate many conjectures concerning super congruences and relate most of them to Euler numbers or Bernoulli numbers. Motivated by our investigation of super congruences, we also raise a conjecture on 7 new series for π2, π-2 and the constant K := ∑k=1^∞(k/3)/k^2 (with (-) the Jacobi symbol), two of which are ∑k=1^∞(10k-3)8k/k2(k^2k)^2(k^3k)=π^2/2and ∑k=1^∞(15k-4)(-27)^k-1/k^3(k^2k)^2(k^3k)=K.