■オイラー・マクローリンの和公式とトッド作用素(その6)
オイラー・マクローリンの和公式を負のベキ和公式に対して適用してみたい.
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[1]Σ1/k^2
f(x)=1/x^2 f^(5)(x)=−6!/x^7
f’(x)=−2/x^3 f^(6)(x)=7!/x^8
f”(x)=6/x^4 f^(7)(x)=−8!/x^9
f^(3)(x)=−24/x^5 f^(8)(x)=9!/x^10
f^(4)(x)=120/x^6 f^(9)(x)=−10!/x^11
Σ(1,n)1/k^2〜∫(1,n)1/x^2dx+(f(n)+f(1))/2+ΣB2k/(2k)!(f^(2k-1)(n)-f^(2k-1)(1))+R
∫(1,n)1/x^2dx=[-1/x]=-1/n+1
(f(n)+f(1))/2=(1/n^2+1)/2
(f'(n)-f'(1))/12=(-2/n^3+2)/12
(f^(3)(n)-f^(3)(1))/720=(-24/n^5+24)/720
(f^(5)(n)-f^(5)(1))/30240=(-6!/n^7+6!)/30240
(f^(7)(n)-f^(7)(1))/1209600=(-8!/n^9+8!)/1209600
Σ1/k^2〜-1/n+1/2n^2-1/6n^3+1/30n^5-1/42n^7n+1/30n^9+1+1/2+1/6-1/30+1/42-1/30+R
−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
1+1/4 =1.25
1+1/4+1/9 =1.36111
1+1/4+1/9+1/25 =1.42361
1+1/4+1/9+1/25+1/36 =1.46361
1+1/4+1/9+1/25+1/36+1/49 =1.49139
1+1/4+1/9+1/25+1/36+1/49+1/64 =1.5118
1+1/4+1/9+1/25+1/36+1/49+1/64+1/81 =1.52742
1+1/4+1/9+1/25+1/36+1/49+1/64+1/81+1/100=1.53977
1+1/4+1/9+1/25+1/36+1/49+1/64+1/81+1/100=1.54977
π^2/6=1.64493
1+1/2+1/6-1/30+1/42-1/30=1.62381
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[2]Σ1/k^3
f(x)=1/x^3 f^(5)(x)=−7!/2x^8
f’(x)=−3/x^4 f^(6)(x)=8!/2x^9
f”(x)=12/x^5 f^(7)(x)=−9!/x^10
f^(3)(x)=−60/x^6 f^(8)(x)=10!/x^11
f^(4)(x)=360/x^7 f^(9)(x)=−11!/x^12
Σ(1,n)1/k^3〜∫(1,n)1/x^3dx+(f(n)+f(1))/2+ΣB2k/(2k)!(f^(2k-1)(n)-f^(2k-1)(1))+R
∫(1,n)1/x^3dx=[-1/2x^2]=-1/2n^2+1/2
(f(n)+f(1))/2=(1/n^3+1)/2
(f'(n)-f'(1))/12=(-3/n^4+3)/12
(f^(3)(n)-f^(3)(1))/720=(-60/n^6+60)/720
(f^(5)(n)-f^(5)(1))/30240=(-2520/n^7+2520)/30240
(f^(7)(n)-f^(7)(1))/1209600=(-181440/n^9+181440)/1209600
Σ1/k^3〜-1/2n^2+1/2n^3-1/4n^4+1/12n^8+・・・+1/2+1/2+1/4-1/12+R
−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
1+1/2^3 =1.125
1+1/2^3+1/3^3 =1.16204
1+1/2^3+1/3^3+1/4^3 =1.17766
1+1/2^3+1/3^3+1/4^3+1/5^3 =1.18566
1+1/2^3+1/3^3+1/4^3+1/5^3+1/6^3 =1.19029
1+1/2^3+1/3^3+1/4^3+1/5^3+1/6^3+1/7^3 =1.19321
1+1/2^3+1/3^3+1/4^3+1/5^3+1/6^3+1/7^3+1/8^3 =1.19516
1+1/2^3+1/3^3+1/4^3+1/5^3+1/6^3+1/7^3+1/8^3+1/9^3 =1.19653
1+1/2^3+1/3^3+1/4^3+1/5^3+1/6^3+1/7^3+1/8^3+1/9^3+1/10^3=1.19753
1/2+1/2+1/4-1/12=1.16667
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[3]Σ1/k^4
f(x)=1/x^4 f^(5)(x)=−8!/6x^9
f’(x)=−4/x^5 f^(6)(x)=9!/6x^10
f”(x)=20/x^6 f^(7)(x)=−10!/6x^11
f^(3)(x)=−120/x^7 f^(8)(x)=11!/6x^12
f^(4)(x)=840/x^8 f^(9)(x)=−12!/x^13
Σ(1,n)1/k^4〜∫(1,n)1/x^4dx+(f(n)+f(1))/2+ΣB2k/(2k)!(f^(2k-1)(n)-f^(2k-1)(1))+R
∫(1,n)1/x^4dx=[-1/3x^3]=-1/3n^3+1/3
(f(n)+f(1))/2=(1/n^4+1)/2
(f'(n)-f'(1))/12=(-4/n^5+4)/12
(f^(3)(n)-f^(3)(1))/720=(-120/n^7+120)/720
(f^(5)(n)-f^(5)(1))/30240=(-6720/n^9+6720)/30240
(f^(7)(n)-f^(7)(1))/1209600=(-604800/n^9+60480040)/1209600
Σ1/k^4〜-1/3n^3+1/2n^4-1/3n^5+1/6n^7+・・・+1/3+1/2+1/3-1/12+R
−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
1+1/2^4 =1.0625
1+1/2^4+1/3^4 =1.07485
1+1/2^4+1/3^4+1/4^4 =1.07875
1+1/2^4+1/3^4+1/4^4+1/5^4 =1.08035
1+1/2^4+1/3^4+1/4^4+1/5^4+1/6^4 =1.08112
1+1/2^4+1/3^4+1/4^4+1/5^4+1/6^4+1/7^4 =1.05154
1+1/2^4+1/3^4+1/4^4+1/5^4+1/6^4+1/7^4+1/8^4 =1.08178
1+1/2^4+1/3^4+1/4^4+1/5^4+1/6^4+1/7^4+1/8^4+1/9^4 =1.08194
1+1/2^4+1/3^4+1/4^4+1/5^4+1/6^4+1/7^4+1/8^4+1/9^4+1/10^4=1.08204
π^4/90=1.08232
1/3+1/2+1/3-1/12=1.08333
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