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 A289343 #13 Jul 03 2017 22:34:40 %S A289343 2,4,112,11292,740754220,361711410384,222595582448849152, %T A289343 258327454310582805036,661821993709898403923269564, %U A289343 10266982973657640119698928948136690256,34586475747666402744018445215769168804860,2847089959666118831608487671650698855934142888811472 %N A289343 a(n) = A289191(prime(n)). %C A289343 The case n=2 is a degenerate polygon (two sides connecting two vertices). The two possibilities are when the edges cross and do not cross. Polygons start at n=3 with a triangle. %H A289343 Marko Riedel, <a href="https://math.stackexchange.com/questions/2097450/">Hexagonal tiles.</a> %H A289343 Marko Riedel, <a href="/A289343/a289343.maple.txt">Maple code for number of tiles using Burnside lemma.</a> %F A289343 a(n) = A289191(prime(n)) %Y A289343 Cf. A289191. %K A289343 nonn %O A289343 1,1 %A A289343 _Marko Riedel_, Jul 02 2017