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%I #16 Jun 28 2024 10:07:28
%S 1,1,3,7,22,83,341,1519,7114,34350
%N Number of polyhexes with n cells.
%H J. V. Knop, K. Szymanski, Ž. Jeričević, and N. Trinajstić, <a href="http://match.pmf.kg.ac.rs/electronic_versions/Match16/match16_119-134.pdf">On the total number of polyhexes</a>, Match, No. 16 (1984), 119-134.
%H Louis Marin, <a href="https://arxiv.org/abs/2406.16413">Counting Polyominoes in a Rectangle b X h</a>, arXiv:2406.16413 [cs.DM], 2024. See p. 145.
%Y See A000228 for another version of this sequence.
%Y Cf. A018190, A038143-A038146.
%K nonn,hard,more
%O 1,3
%A _N. J. A. Sloane_.