In this paper we prove that if f ∈ C ([-π, π]^2) and the function f is bounded partial p-variation for some p ∈[1, +∞), then the double trigonometric Fourier series of a function f is uniformly (C;-α,-β) ...In this paper we prove that if f ∈ C ([-π, π]^2) and the function f is bounded partial p-variation for some p ∈[1, +∞), then the double trigonometric Fourier series of a function f is uniformly (C;-α,-β) summable (α+β 〈 1/p,α,β 〉 0) in the sense of Pringsheim. If α + β ≥ 1/p, then there exists a continuous function f0 of bounded partial p-variation on [-π,π]^2 such that the Cesàro (C;-α,-β) means σn,m^-α,-β(f0;0,0) of the double trigonometric Fourier series of f0 diverge over cubes.展开更多
文摘In this paper we prove that if f ∈ C ([-π, π]^2) and the function f is bounded partial p-variation for some p ∈[1, +∞), then the double trigonometric Fourier series of a function f is uniformly (C;-α,-β) summable (α+β 〈 1/p,α,β 〉 0) in the sense of Pringsheim. If α + β ≥ 1/p, then there exists a continuous function f0 of bounded partial p-variation on [-π,π]^2 such that the Cesàro (C;-α,-β) means σn,m^-α,-β(f0;0,0) of the double trigonometric Fourier series of f0 diverge over cubes.