A013475 - OEIS

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A013475

Coefficient of [x^(4*n+2)] in e.g.f. sinh(cosh(x) - cos(x)).

2, 122, 35282, 27747722, 46640267042, 144890071612442, 754330752297972722, 6132809160585358346282, 73810833499088630365101122, 1261113117777698263842030054842, 29574312688030228358559752005274642

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OFFSET

0,1

LINKS

Table of n, a(n) for n=0..10.

EXAMPLE

(2/2!)*x^2 + (122/6!)*x^6 + (35282/10!)*x^10 + (27747722/14!)*x^14 + ...

MATHEMATICA

With[{nn=30}, Take[Abs[CoefficientList[Series[Sinh[Cos[x]-Cosh[x]], {x, 0, nn}], x] Range[0, nn]!], {3, -1, 4}]] (* Harvey P. Dale, Aug 08 2017 *)

DeleteCases[ Range[0, 42]! CoefficientList[ Series[ Sinh[Cosh[x] - Cos[x]], {x, 0, 42}], x], 0] (* Robert G. Wilson v, Aug 06 2018 *)

CROSSREFS

Sequence in context: A056638 A222873 A325889 * A013471 A370967 A249497

Adjacent sequences: A013472 A013473 A013474 * A013476 A013477 A013478

KEYWORD

nonn

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

EXTENSIONS

More terms from Harvey P. Dale, Aug 08 2017

More terms and title improved by Sean A. Irvine, Aug 06 2018

STATUS

approved