cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A126202 Number of pointed polyominoes with n cells.

Original entry on oeis.org

1, 1, 1, 4, 12, 46, 172, 689, 2763, 11241, 45706, 186346, 759375, 3095191, 12610825, 51370336, 209194923, 851712069, 3466881944
Offset: 0

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Author

David Applegate and N. J. A. Sloane, Mar 09 2007

Keywords

Comments

Number of pairs (P,C), where P is a polyomino with n cells (cf. A000105) and C runs through the orbit representatives of cells in P under the automorphism group of P.

Examples

			a(4) = 12: polyomino and number of orbits on points:
XXXX..XXX..XXX..XX...XX
......X.....X....XX..XX
(2)...(4)..(3)..(2)..(1): total 12
		

Crossrefs