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A143047 G.f. satisfies: A(x) = 1 + x*A(-x)^4. 4
1, 1, -4, -10, 84, 265, -2604, -8900, 94692, 337940, -3767312, -13812674, 158785964, 593029550, -6967201736, -26372738120, 314904180100, 1204230041900, -14560722724912, -56130528427400, 685514219386576, 2659770565898729, -32749512944380172 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..22.

FORMULA

G.f. satisfies: A(x) = 1 + x*(1 - x*A(x)^4)^4.

G.f. satisfies: [A(x)^5 + A(-x)^5]/2 = [A(x)^4 + A(-x)^4]/2.

EXAMPLE

A(x) = 1 + x - 4*x^2 - 10*x^3 + 84*x^4 + 265*x^5 - 2604*x^6 - 8900*x^7 +...

A(x)^4 = 1 + 4*x - 10*x^2 - 84*x^3 + 265*x^4 + 2604*x^5 - 8900*x^6 -...

A(x)^5 = 1 + 5*x - 10*x^2 - 120*x^3 + 265*x^4 + 3906*x^5 - 8900*x^6 -...

Note that a bisction of A^5 equals a bisection of A^4.

PROG

(PARI) a(n)=local(A=x+x*O(x^n)); for(i=0, n, A=1+x*subst(A, x, -x)^4); polcoeff(A, n)

CROSSREFS

Cf. A143045, A143046, A143048, A143049, A213335.

Sequence in context: A171754 A215872 A059919 * A156329 A266839 A203179

Adjacent sequences:  A143044 A143045 A143046 * A143048 A143049 A143050

KEYWORD

sign

AUTHOR

Paul D. Hanna, Jul 19 2008

STATUS

approved

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Last modified May 12 12:34 EDT 2021. Contains 343823 sequences. (Running on oeis4.)