OFFSET
0,2
COMMENTS
Binomial transform of A081921
Generally, if e.g.f. = exp(p*x)/sqrt(1-x^2), then a(n) ~ n^n * (exp(p)+(-1)^n*exp(-p)) / exp(n). - Vaclav Kotesovec, Feb 04 2014
FORMULA
E.g.f.: exp(4x)/sqrt(1-x^2).
D-finite with recurrence: -a(n) + 4*a(n-1) + (n-1)^2*a(n-2) - 4*(n-1)*(n-2)*a(n-3) = 0. - R. J. Mathar, Nov 09 2012
a(n) ~ n^n * (exp(4) + (-1)^n*exp(-4)) / exp(n). - Vaclav Kotesovec, Feb 04 2014
MATHEMATICA
With[{nn=20}, CoefficientList[Series[Exp[4x]/Sqrt[1-x^2] , {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, May 07 2012 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Apr 01 2003
STATUS
approved