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A223026 G.f. A(x) satisfies: A(x)^8 = A(x^2)^4 + 8*x. 6
1, 1, -3, 14, -76, 441, -2678, 16813, -108093, 707451, -4696017, 31530792, -213715953, 1460072247, -10042361784, 69473047716, -483046768116, 3373552141194, -23653214175084, 166422650191122, -1174621198245837, 8314055808436788, -58998774106863513 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

The limit a(n+1)/a(n) seems to be near -7.46...

LINKS

Paul D. Hanna, Table of n, a(n) for n = 0..300

FORMULA

Self-convolution yields A228711.

EXAMPLE

G.f.: A(x) = 1 + x - 3*x^2 + 14*x^3 - 76*x^4 + 441*x^5 - 2678*x^6 +-...

where

A(x)^8 = 1 + 8*x + 4*x^2 - 6*x^4 + 24*x^6 - 117*x^8 + 612*x^10 - 3426*x^12 +-...

A(x^2)^4 = 1 + 4*x^2 - 6*x^4 + 24*x^6 - 117*x^8 + 612*x^10 - 3426*x^12 +-...

A(x)^2 = 1 + 2*x - 5*x^2 + 22*x^3 - 115*x^4 + 646*x^5 - 3822*x^6 +-...

PROG

(PARI) {a(n)=local(A=1+x); for(i=1, #binary(n), A=(subst(A, x, x^2)^4+8*x+x*O(x^n))^(1/8)); polcoeff(A, n, x)}

for(n=0, 20, print1(a(n), ", "))

CROSSREFS

Cf. A107086, A107089, A228711, A228712.

Sequence in context: A246455 A133798 A100937 * A198702 A198621 A198649

Adjacent sequences:  A223023 A223024 A223025 * A223027 A223028 A223029

KEYWORD

sign

AUTHOR

Paul D. Hanna, Mar 11 2013

STATUS

approved

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Last modified February 20 08:26 EST 2018. Contains 299377 sequences. (Running on oeis4.)