cp's OEIS Frontend

A112121 G.f. A(x) satisfies A(A(A(..(A(x))..))) = B(x) (10th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,..,10}, with B(0) = 0.

%I A112121 #6 Mar 14 2015 01:08:43
%S A112121 1,1,-8,104,-1619,27437,-482626,8553639,-149434331,2527339944,
%T A112121 -40748011084,619534898788,-8892967520397,124088656925363,
%U A112121 -1797865061490547,28140512084643142,-424643873334235802,4269156014010214570,19251023484926369328,-1456780704021544219838
%N A112121 G.f. A(x) satisfies A(A(A(..(A(x))..))) = B(x) (10th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,..,10}, with B(0) = 0.
%e A112121 A(x) = x + x^2 - 8*x^3 + 104*x^4 - 1619*x^5 + 27437*x^6 +...
%e A112121 where A(A(A(A(A(A(A(A(A(A(x)))))))))) =
%e A112121 x + 10*x^2 + 10*x^3 + 5*x^4 + 10*x^5 + 5*x^6 + 8*x^7 +...
%e A112121 is the g.f. of A112120.
%o A112121 (PARI) {a(n,m=10)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); return(polcoeff(F,n,x)))}
%Y A112121 Cf. A112120, A112104-A112119, A112122-A112127.
%K A112121 sign
%O A112121 1,3
%A A112121 _Paul D. Hanna_, Aug 27 2005