A193479 G.f. A(x) satisfies: 1+x = Sum_{n>=0} A(x)^n/sf(n), where A(x) = Sum_{n>=1} a(n)*x^n/sf(n), and sf(n) = Product_{k=0..n} k! is the superfactorial of n (A000178).
1, -1, 5, -121, 16199, -13857481, 86631572159, -4470597876144961, 2126428452257713430399, -10305779379533133607589385601, 557802385738943120790269629003660799, -366846102335019802908345392106358106684889601, 3169417347948517943104654704100947667168800468999705599
Offset: 1
Keywords
Examples
A(x) = x - x^2/(1!*2!) + 5*x^3/(1!*2!*3!) - 121*x^4/(1!*2!*3!*4!) + 16199*x^5/(1!*2!*3!*4!*5!) - 13857481*x^6/(1!*2!*3!*4!*5!*6!) +...+ a(n)*x^n/sf(n) +... where 1+x = 1 + A(x) + A(x)^2/(1!*2!) + A(x)^3/(1!*2!*3!) + A(x)^4/(1!*2!*3!*4!) + A(x)^5/(1!*2!*3!*4!*5!) + A(x)^6/(1!*2!*3!*4!*5!*6!) +...+ A(x)^n/sf(n) +... and sf(n) = 0!*1!*2!*3!*...*(n-1)!*n!.
Programs
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PARI
{a(n)=local(A=sum(m=1,n-1,a(m)*x^m/prod(k=0,m,k!))+O(x^(n+2))); prod(k=0,n,k!)*polcoeff(1+x-sum(m=0,n,A^m/prod(k=0,m,k!)),n)}