A009497 Expansion of e.g.f. sin(sinh(x)*sin(x))/2 in odd powers of x^2.

1, -64, 25216, -31711744, 93380755456, -538721831747584, 5434440423098023936, -88353705160970793385984, 2179843711161864280506105856, -77903078128153520290915516678144, 3885493817309637834095425199974383616, -262391914253566550682675647373292878168064

Offset

0,2

Links

Andrew Howroyd, Table of n, a(n) for n = 0..100

Example

x^2/2! - 64*x^6/6! + 25216*x^10/10! - 31711744*x^14/14! ...

Mathematica

With[{nn=50}, Take[CoefficientList[Series[Sin[Sinh[x]*Sin[x]]/2, {x, 0, nn}], x] Range[0, nn]!, {3, -1, 4}]] (* Harvey P. Dale, Oct 08 2017 *)

Prog

(PARI) seq(n)={my(A=O(x^(4*n+2))); Vec(substpol(serlaplace( sin(sinh(x+A)*sin(x+A))/2 )/x^2, x^4, x))} \\ Andrew Howroyd, Jan 11 2025

Crossrefs

Cf. A012524.

Sequence in context: A082502 A052200 A146517 * A145258 A202911 A013743

Adjacent sequences: A009494 A009495 A009496 * A009498 A009499 A009500

Keyword

sign

Author

R. H. Hardin

Extensions

Extended by Olivier Gérard, Mar 15 1997

Prior Mathematica program replaced by Harvey P. Dale, Oct 08 2017

a(10) onwards from Andrew Howroyd, Jan 11 2025

Status

approved