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Number of rooted 2-dimensional polyominoes with n pentagonal cells, with no symmetries removed.
3

%I #14 Sep 21 2017 09:03:16

%S 1,5,30,180,1075,6366,37520,220500,1293615,7581240,44398387,259881960,

%T 1520633270,8895116230

%N Number of rooted 2-dimensional polyominoes with n pentagonal cells, with no symmetries removed.

%C Number of polypents (like polyominoes, with pentagons) with n cells. These are anchored polypents, with no culling for reflection or rotation (or translation) isomorphism.

%D Dan Hoey, Bill Gosper and Richard C. Schroeppel, Discussions in Math-Fun Mailing list, circa Jul 13 1999.

%H R. C. Schroeppel, <a href="http://www.experimentalmath.info/workshop2004/schroeppel-talk.pdf">A few mathematical experiments</a>

%Y A row of A094166.

%K nonn

%O 1,2

%A Richard C. Schroeppel, Feb 13 2002

%E More terms from _N. J. A. Sloane_, May 06 2004

%E Edited by _N. J. A. Sloane_, Sep 15 2008 at the suggestion of _R. J. Mathar_