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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. 3
1, 1, -8, 104, -1619, 27437, -482626, 8553639, -149434331, 2527339944, -40748011084, 619534898788, -8892967520397, 124088656925363, -1797865061490547, 28140512084643142, -424643873334235802, 4269156014010214570, 19251023484926369328, -1456780704021544219838 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

A(x) = x + x^2 - 8*x^3 + 104*x^4 - 1619*x^5 + 27437*x^6 +...

where A(A(A(A(A(A(A(A(A(A(x)))))))))) =

x + 10*x^2 + 10*x^3 + 5*x^4 + 10*x^5 + 5*x^6 + 8*x^7 +...

is the g.f. of A112120.

PROG

(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)))}

CROSSREFS

Cf. A112120, A112104-A112119, A112122-A112127.

Sequence in context: A282185 A354064 A106260 * A141383 A034300 A266044

Adjacent sequences:  A112118 A112119 A112120 * A112122 A112123 A112124

KEYWORD

sign

AUTHOR

Paul D. Hanna, Aug 27 2005

STATUS

approved

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Last modified May 21 00:36 EDT 2022. Contains 353886 sequences. (Running on oeis4.)