login
A012639
cos(arcsinh(x)*cos(x))=1-1/2!*x^2+17/4!*x^4-385/6!*x^6+15073/8!*x^8...
0
1, -1, 17, -385, 15073, -1010945, 101590513, -14396384769, 2765830859457, -694784293696513, 221386930443511505, -87298037019243856513, 41742102489497599699873, -23796035609379191857799425
OFFSET
0,3
FORMULA
a(n) ~ (-1)^n * sinh(Pi*cosh(1)/2) * cosh(1) * 2^(2*n) * n^(2*n-1) / exp(2*n). - Vaclav Kotesovec, Nov 01 2013
MATHEMATICA
Table[n!*SeriesCoefficient[Cos[ArcSinh[x]*Cos[x]], {x, 0, n}], {n, 0, 40, 2}] (* Vaclav Kotesovec, Nov 01 2013 *)
CROSSREFS
Sequence in context: A132541 A159244 A318043 * A350926 A327732 A012200
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved