A007301 From expansion of exp(sin x).

1, 1, -3, -3, 217, -2951, 5973, 1237173, -52635599, 1126610929, 20058390573, -3920482183827, 256734635981833, -8529964147714967, -383670903748980603, 99786978811973617701, -10380441423510120242591, 594094494902602207843297

Offset: 0

Author

N. J. A. Sloane

Keywords

• sign
• easy

References

• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Programs

Mathematica

With[{nn=40},Take[CoefficientList[Series[Exp[Sin[x]],{x,0,nn}],x] Range[ 0,nn]!,{1,-1,2}]] (* Harvey P. Dale, Dec 22 2018 *)

Formula

a(n) = A002017(2n).

Extensions

Extended with signs by Christian G. Bower, Oct 1998