A123117 A063865(4n-3).

2, 8, 70, 722, 8220, 99820, 1265204, 16547220, 221653776, 3025553180, 41931984034, 588491482334, 8346638665718, 119447839104366, 1722663727780132, 25011714460877474, 365301750223042066, 5363288299585278800

Offset

1,1

Links

Ray Chandler, Table of n, a(n) for n = 1..835 (terms < 10^1000)

Formula

a(n) = 2*A104456(n).

Crossrefs

Cf. A063865, A060468, A104456.

Sequence in context: A239843 A099729 A373062 * A330676 A062733 A180687

Adjacent sequences: A123114 A123115 A123116 * A123118 A123119 A123120

Keyword

nonn

Author

N. J. A. Sloane, Jul 07 2008

Status

approved