A012686 sec(tanh(x)*arctan(x))=1+12/4!*x^4-480/6!*x^6+35280/8!*x^8...

1, 0, 12, -480, 35280, -4208640, 737643456, -178203637248, 56744323733760, -23028982493429760, 11602867906455268352, -7105927543880909185024, 5198792960623369943994368, -4478214849312972324010721280

Offset

0,3

Links

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

Crossrefs

Sequence in context: A012685 A012465 A012394 * A012466 A344113 A229634

Adjacent sequences: A012683 A012684 A012685 * A012687 A012688 A012689

Keyword

sign

Author

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

Status

approved