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A177388 O.g.f.: Sum_{n>=0} Product_{k=1..n} sin(k*asin(2x)). 2
1, 2, 8, 48, 368, 3488, 39408, 517536, 7747552, 130224448, 2428303280, 49745334816, 1110519910176, 26832869319872, 697671946188128, 19422303020653632, 576390053072381888, 18164695560213480064 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 0..260

FORMULA

O.g.f.: A(x) = G(asin(2x)) where G(x) = e.g.f. of A177387.

a(n) ~ c * (4/(Pi*log(2)))^n * n! * n^(1/6), where c = 1.01529686... . - Vaclav Kotesovec, Nov 04 2014

EXAMPLE

O.g.f.: A(x) = 1 + 2*x + 8*x^2 + 48*x^3 + 368*x^4 + 3488*x^5 +...

Let G(x) be the e.g.f. of A177387:

G(x) = 1 + x + 4*x^2/2! + 35*x^3/3! + 536*x^4/4! +...

then A(x) = G(asin(2*x)).

PROG

(PARI) {a(n)=local(X=x+x*O(x^n), Ogf); Ogf=sum(m=0, n, prod(k=1, m, sin(k*asin(2*X)))); polcoeff(Ogf, n)}

CROSSREFS

Cf. A177387.

Sequence in context: A003576 A225042 A095989 * A211196 A219613 A124453

Adjacent sequences:  A177385 A177386 A177387 * A177389 A177390 A177391

KEYWORD

nonn

AUTHOR

Paul D. Hanna, May 15 2010

STATUS

approved

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Last modified December 19 21:57 EST 2014. Contains 252240 sequences.