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 A320944 #20 Nov 11 2018 04:51:29 %S A320944 1,6,24,200,3216 %N A320944 a(n) is the number of perimeter tiles among all rhombic tilings of the 2n-gon. %C A320944 Tiles and polygons all have sides of length 1, as in A006245. %H A320944 B. E. Tenner, <a href="https://arxiv.org/abs/1811.00082">Tiling-based models of perimeter and area</a>, arXiv:1811.00082 [math.CO], 2018. %F A320944 a(n) = 2*n*A320945(n) for n > 2. %e A320944 a(4) = 24 because among the eight rhombic tilings of the octagon, 24 perimeter rhombi appear. %Y A320944 Cf. A320945, A320946, A006245. %K A320944 nonn,more %O A320944 2,2 %A A320944 _Bridget Tenner_, Oct 24 2018