Number of staircase polygons on the square lattice with perimeter 2n and one (possibly rotated) staircase polygonal hole.
1, 12, 94, 604, 3461, 18412, 93016, 452500, 2139230, 9890404, 44921002
2 seqfan posts
Sat Feb 14 17:55:18 CET 2009 [seqfan] Re: Staircase Polygons (with a Rotate...), a correction