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A051738
Number of rooted 2-dimensional polyominoes with n pentagonal cells, with no symmetries removed.
3
1, 5, 30, 180, 1075, 6366, 37520, 220500, 1293615, 7581240, 44398387, 259881960, 1520633270, 8895116230
OFFSET
1,2
COMMENTS
Number of polypents (like polyominoes, with pentagons) with n cells. These are anchored polypents, with no culling for reflection or rotation (or translation) isomorphism.
REFERENCES
Dan Hoey, Bill Gosper and Richard C. Schroeppel, Discussions in Math-Fun Mailing list, circa Jul 13 1999.
CROSSREFS
A row of A094166.
Sequence in context: A105481 A242157 A094167 * A052934 A136785 A227383
KEYWORD
nonn
AUTHOR
Richard C. Schroeppel, Feb 13 2002
EXTENSIONS
More terms from N. J. A. Sloane, May 06 2004
Edited by N. J. A. Sloane, Sep 15 2008 at the suggestion of R. J. Mathar
STATUS
approved