A012078 arctan(arcsin(tan(x)))=x+1/3!*x^3+9/5!*x^5+393/7!*x^7+33009/9!*x^9...

1, 1, 9, 393, 33009, 4410033, 872617017, 240500373753, 88094910348129, 41401437242599905, 24287046275803547625, 17396048031084882189033, 14941352753081733849348945, 15157924050230673397966293393

Offset

0,3

Links

Table of n, a(n) for n=0..13.

Mathematica

With[{nn=30}, Take[CoefficientList[Series[ArcTan[ArcSin[Tan[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, May 07 2021 *)

Crossrefs

Sequence in context: A297738 A225988 A012191 * A332139 A266924 A157599

Adjacent sequences: A012075 A012076 A012077 * A012079 A012080 A012081

Keyword

nonn

Author

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

Status

approved