A057417 Number of staircase polygons of area n with any number of (staircase polygon) holes on square lattice (not allowing rotations).

1, 2, 4, 9, 20, 46, 105, 243, 561, 1303, 3026, 7047, 16419, 38314, 89454, 209056, 488810, 1143686, 2677074, 6269438, 14687799, 34423317, 80702234, 189258382, 443958607, 1041704375, 2444830929, 5739200960, 13475465449

Offset

1,2

Links

I. Jensen, Table of n, a(n) for n = 1..76 (from link below)

I. Jensen, More terms

Crossrefs

Sequence in context: A036617 A367713 A007902 * A191653 A191827 A000968

Adjacent sequences: A057414 A057415 A057416 * A057418 A057419 A057420

Keyword

nonn

Author

N. J. A. Sloane, Aug 30 2000

Status

approved