■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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