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%I #7 Sep 21 2017 09:03:19
%S 1,7,42,252,1505,8946,53165,315980,1878597,11171930,66456082,
%T 395399760,2352979538,14004512886
%N Number of rooted 2-dimensional polyominoes with n heptagonal cells, with no symmetries removed.
%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 _N. J. A. Sloane_, May 06 2004