A012696 arctan(tanh(x)*tanh(x))=2/2!*x^2-16/4!*x^4+32/6!*x^6+18944/8!*x^8...

2, -16, 32, 18944, -1904128, 41160704, 41418432512, -13226611572736, 1026478445821952, 1419327244545818624, -990157599155377143808, 185269154824838954614784, 314145305969818487050207232

Offset

0,1

Links

Table of n, a(n) for n=0..12.

Crossrefs

Sequence in context: A279034 A120069 A018975 * A012392 A009819 A189332

Adjacent sequences: A012693 A012694 A012695 * A012697 A012698 A012699

Keyword

sign

Author

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

Status

approved