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A057412 Number of staircase polygons of perimeter 2n with 3 (staircase polygon) holes on square lattice (not allowing rotations). 1
28, 884, 15266, 191688, 1964414, 17460336, 139630696, 1029053248, 7106319403, 46539551768, 291656481886, 1761110727936, 10301848134999, 58631700564776, 325806962400428, 1772760905500304, 9467673927142781 (list; graph; refs; listen; history; text; internal format)
OFFSET
16,1
LINKS
I. Jensen, Table of n, a(n) for n = 16..67 (from link below)
I. Jensen, More terms
CROSSREFS
Sequence in context: A326279 A278195 A095656 * A160263 A129461 A239336
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 30 2000
STATUS
approved

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Last modified June 18 04:26 EDT 2024. Contains 373468 sequences. (Running on oeis4.)