A012851 sec(sec(x)*arctanh(x))=1+1/2!*x^2+25/4!*x^4+1225/6!*x^6+108113/8!*x^8...

1, 1, 25, 1225, 108113, 15283505, 3167087273, 904365439289, 340377095938337, 163284306442648801, 97251848546749385145, 70412470931263247515689, 60905917762268697815507057, 62032377805368358044198610705

Offset

0,3

Links

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

Crossrefs

Sequence in context: A120694 A012809 A014769 * A181719 A096330 A174751

Adjacent sequences: A012848 A012849 A012850 * A012852 A012853 A012854

Keyword

nonn

Author

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

Status

approved