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 A236583 #10 Nov 28 2016 01:48:07 %S A236583 1,1,4,11,33,96,281,821,2400,7015,20505,59936,175193,512089,1496836, %T A236583 4375251,12788857,37381824,109267057,319387565,933569728,2728823951, %U A236583 7976351345,23314871872,68149361393 %N A236583 The number of tilings of an 8 X (3n) floor with 2 X 3 hexominoes. %C A236583 Tilings are counted irrespective of internal symmetry: Tilings that match each other after rotations and/or reflections are counted with their multiplicity. %H A236583 R. J. Mathar, <a href="http://arxiv.org/abs/1311.6135">Paving rectangular regions...</a>, arXiv:1311.6135, Table 51. %H A236583 R. J. Mathar, <a href="http://arxiv.org/abs/1406.7788">Tilings of Rectangular Regions by Rectangular Tiles: Counts Derived from Transfer Matrices</a>, arXiv:1406.7788 [math.CO], eq. (34). %H A236583 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (3,0,-1,1). %F A236583 G.f.: (-1+x)^2/(x^3-x^4+1-3*x). %p A236583 g := (-1+x)^2/(x^3-x^4+1-3*x) ; %p A236583 taylor(%,x=0,30) ; %p A236583 gfun[seriestolist](%) ; %Y A236583 Cf. A000079 (5 X n floor), A182097 (6 X n floor), A000244 (7 X n floor), A236584 (9 x 2n floor) %K A236583 easy,nonn %O A236583 0,3 %A A236583 _R. J. Mathar_, Jan 29 2014