S0=Σ1=n
S1=Σk=n(n+1)/2
S2=Σk^2=n(n+1)(2n+1)/6
S3=Σk^3=n^2(n+1)^2/4・・・とおく.
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n=S0
n^2=2S1-S0
n^3=3S2-3S1+S0
n^4=4S3-6S2+4S1-S0
S0=S0
2S1^2=2S3
4S1^3=3S5+S3
8S1^4=4S7+4S5