■オイラー・マクローリンの和公式とトッド作用素(その5)
オイラー・マクローリンの和公式をベキ和公式に対して適用してみたい.
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[1]Σk
f(x)=x f^(5)(x)=0
f’(x)=1 f^(6)(x)=0
f”(x)=0 f^(7)(x)=0
f^(3)(x)=0 f^(8)(x)=0
f^(4)(x)=0 f^(9)(x)=0
Σ(0,n)k〜∫(0,n)xdx+(f(n)+f(0))/2+ΣB2k/(2k)!(f^(2k-1)(n)-f^(2k-1)(0))+R
∫(0,n)xdx=[x^2/2]=n^2/2
(f(n)+f(0))/2=n/2
(f'(n)-f'(0))/12=0
(f^(3)(n)-f^(3)(0))/720=0
(f^(5)(n)-f^(5)(0))/30240=0
(f^(7)(n)-f^(7)(0))/1209600=0
Σk〜(n^2/2+n/2=n(n+1)/2
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[2]Σk^2
f(x)=x^2 f^(5)(x)=0
f’(x)=2x f^(6)(x)=0
f”(x)=x f^(7)(x)=0
f^(3)(x)=1 f^(8)(x)=0
f^(4)(x)=0 f^(9)(x)=0
Σ(0,n)k^2〜∫(0,n)x^2dx+(f(n)+f(0))/2+ΣB2k/(2k)!(f^(2k-1)(n)-f^(2k-1)(0))+R
∫(0,n)x^2dx=[x^3/3]=n^3/3
(f(n)+f(0))/2=n^2/2
(f'(n)-f'(0))/12=n/12
(f^(3)(n)-f^(3)(0))/720=0
(f^(5)(n)-f^(5)(0))/30240=0
(f^(7)(n)-f^(7)(0))/1209600=0
Σk^2〜(n^3/3+n^2/2+n/12=n(n+1)(2n+1)/6
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[3]Σk^3
f(x)=x^3 f^(5)(x)=0
f’(x)=3x^2 f^(6)(x)=0
f”(x)=6x f^(7)(x)=0
f^(3)(x)=6 f^(8)(x)=0
f^(4)(x)=0 f^(9)(x)=0
Σ(0,n)k^3〜∫(0,n)x^3dx+(f(n)+f(0))/2+ΣB2k/(2k)!(f^(2k-1)(n)-f^(2k-1)(0))+R
∫(0,n)x^3dx=[x^4/4]=n^4/4
(f(n)+f(0))/2=n^3/2
(f'(n)-f'(0))/12=3/12・n^2
(f^(3)(n)-f^(3)(0))/720=0
(f^(5)(n)-f^(5)(0))/30240=0
(f^(7)(n)-f^(7)(0))/1209600=0
Σk^3〜(n^4/4+n^3/2+n^2/4={n(n+1)/2}^2
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