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A057413 Number of staircase polygons of perimeter 2n with any number of (staircase polygon) holes on square lattice (not allowing rotations). 1
1, 2, 5, 14, 42, 132, 430, 1442, 4956, 17400, 62251, 226506, 836911, 3136182, 11906908, 45761338, 177903128, 699167112, 2776219871, 11132523840, 45062497156, 184057276510, 758328417263, 3150593560374, 13195743501195 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

LINKS

I. Jensen, Table of n, a(n) for n = 1..51 (from link below)

I. Jensen, More terms

CROSSREFS

Sequence in context: A120588 A168491 A000108 * A126567 A125501 A126569

Adjacent sequences:  A057410 A057411 A057412 * A057414 A057415 A057416

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Aug 30 2000

STATUS

approved

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Last modified December 12 15:01 EST 2017. Contains 295939 sequences.