A057414 Number of staircase polygons of area n with one (staircase polygon) hole on square lattice (not allowing rotations).

1, 4, 18, 62, 205, 624, 1841, 5214, 14448, 39118, 104281, 273900, 711416, 1828950, 4663203, 11801056, 29677044, 74209404, 184655403, 457446252, 1128794669, 2775534900, 6802886782, 16625602146, 40524317635

Offset: 8

Author

N. J. A. Sloane, Aug 30 2000

Keywords

• nonn

Links

• I. Jensen, Table of n, a(n) for n = 8..113 (from link below)
• I. Jensen, More terms