A084356 A000055(n+2)-A023359(n).

1, 0, 0, 0, 0, 1, 5, 16, 50, 137, 377, 995, 2617, 6785, 17630, 45646, 118595, 308645, 806617, 2115455, 5572438, 14737430, 39139779, 104354064, 279293860, 750182992, 2021884234, 5466813137, 14826008106, 40322237818, 109957234707

Offset: 0

Author

Jon Perry, Jun 22 2003

Keywords

• nonn

Crossrefs

Cf. A000055, A023359.