Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #11 Dec 05 2014 05:06:17
%S 1,1,3,6,12,36,60,209,387,1054,1468,6895,7001,23920,49496,126732,
%T 146046,638800,647502,2772935,4162861
%N Number of polyhexes with n cells that tile the plane by translation.
%D Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Section 9.4.
%H Joseph Myers, <a href="http://www.polyomino.org.uk/mathematics/polyform-tiling/">Polyhex tiling</a>
%Y Cf. A070766, A075208, A075209, A075210, A075211, A075212, A075213, A075214, A075215, A075198, A075216.
%K hard,nonn
%O 1,3
%A _Joseph Myers_, Sep 08 2002
%E More terms from _Joseph Myers_, Nov 08 2003
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 05 2007