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A120975 G.f. satisfies: A(x) = 1 + x*A(x)^4*[A(x*A(x)^4)]^4. 4
1, 1, 8, 108, 1888, 38798, 894308, 22517256, 609112756, 17507219813, 530495478900, 16850219461706, 558608940038072, 19263089278722726, 689119527976265884, 25519081467271687938, 976447764170903902364 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..16.

FORMULA

G.f. A(x) satisfies: A(x) = G(G(x)-1), A(G(x)-1) = G(A(x)-1), A(x) = G(x*A(x)^4) and A(x/G(x)^4) = G(x), where G(x) is the g.f. of A120974 and satisfies G(x/G(x)^4) = 1 + x.

PROG

(PARI) {a(n)=local(A, G=[1, 1]); for(i=1, n, G=concat(G, 0); G[ #G]=-Vec(subst(Ser(G), x, x/Ser(G)^4))[ #G]); A=Vec(((Ser(G)-1)/x)^(1/4)); A[n+1]}

CROSSREFS

Cf. A120974; variants: A120971, A120973, A120977.

Sequence in context: A272497 A215129 A234571 * A193678 A265277 A184267

Adjacent sequences:  A120972 A120973 A120974 * A120976 A120977 A120978

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Jul 20 2006

STATUS

approved

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Last modified January 18 19:50 EST 2020. Contains 331030 sequences. (Running on oeis4.)