n=30;(*雷恩和斯隆的算法*)
S4[f,h,x^2]:=f[h,x]^4/24+f[h,x]^2 f[h,x^2]/4+f[h,x]f[h,x^3]/3+f[h,x^2]^2/8+f[h,x^4]/4;
T[-1,z_9]:=1;T[h,z}:=T[h,z]=表[z^k,{k,0,n}]。取[CoefficientList[z^(n+1)+1+S4[T,h-1,z]z,z],n+1];
Sum[取[CoefficientList[z^(n+1)+(T[h,z]-T[h-1,z])^2/2+(T[h,z^2]-T[h-1,z^2])/2,z],n+1],{h,0,n/2}](*罗伯特A.罗素2018年9月15日*)
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