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%I #20 Dec 15 2021 00:20:04
%S 1,3,11,44,184,784,3370,14544,62862,271804,1175133,5079516,21951384,
%T 94847528,409767878,1770177486
%N Number of row convex polyhexes with n cells.
%C A polyhex is considered to be row convex if cells take contiguous positions in each row. (Multiple cells in a row are not connected.)
%H Adam Gruber, <a href="https://devweb3000.cis.strath.ac.uk/~xpb16190/LatticeAnimals/LatticeAnimals.jar">Java program to count lattice animals</a>.
%e The only pentahexes that are not row convex are the shallow V shape and its 180-degree rotation. So a(5) = A001207(5) - 2 = 184.
%Y Cf. A001207 (fixed polyhexes), A059716 (column convex polyhexes).
%K nonn,more
%O 1,2
%A _David Bevan_, Sep 18 2018