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;
S5[f,h,x^2]:=f[h,x]^5/120+f[h,x]^3 f[h,x^2]/12+f[h,x]^2 f[h,x^3]/6+f[h,x]f[h,x^2]^2/8+f[h,x]f[h,x^4]/4+f[h,x^2]f[h,x^3]/6+f[h,x^5]/5;
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)+S5[T,h-1,z]z-S5[T,h-2,z]z-(T[h-1,z]-T[h-2,z])(T[h-1,z]-1),z],n+1],{h,1,n/2}]+PadRight[{0,1},n+1](*罗伯特A.罗素2018年9月15日*)
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