A057416 Number of staircase polygons of area n with 3 (staircase polygon) holes on square lattice (not allowing rotations).

4, 30, 184, 894, 3885, 15386, 56956, 199620, 669702, 2166462, 6798186, 20786496, 62160079, 182336358, 525931258, 1494726848, 4192885357, 11625457180, 31899800729, 86717361496, 233754981005, 625311996048

Offset

18,1

Links

I. Jensen, Table of n, a(n) for n = 18..89 (from link below)

I. Jensen, More terms

Crossrefs

Sequence in context: A317567 A132849 A115867 * A089154 A113450 A344399

Adjacent sequences: A057413 A057414 A057415 * A057417 A057418 A057419

Keyword

nonn

Author

N. J. A. Sloane, Aug 30 2000

Status

approved