This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A197554 #9 Dec 05 2014 02:52:23 %S A197554 1,2,7,24,98,415,1846,8378,38764,181482,858387,4091763,19635210, %T A197554 94749398 %N A197554 Number of free poly-IH14-tiles (holes allowed) with n cells. %C A197554 Equivalently, polyhexes where two polyhexes are considered equivalent if and only if they are related by a translation or a reflection or glide reflection in a line in one fixed direction parallel to the sides of the hexagons. %D A197554 Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Sections 6.2 and 9.4. %Y A197554 Cf. A000228, A001207, A006535, A057973, A197549, A197550, A197551, A197552, A197553. %K A197554 hard,nonn %O A197554 1,2 %A A197554 _Joseph Myers_, Oct 16 2011