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 A193175 #17 Mar 30 2012 16:52:03 %S A193175 4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38,40,42,44,48,50,54, %T A193175 60,66,70,84,90 %N A193175 Numbers n such that there exists a two-dimensional generalized Bravais lattice with n-fold symmetry. %C A193175 The complete list of 29 terms is shown. These are the values of 2n such that A193179(n)=1. %D A193175 Mermin, N. David; Rokhsar, Daniel S.; and Wright, David C.; Beware of 46-fold symmetry: the classification of two-dimensional quasicrystallographic lattices. Phys. Rev. Lett. 58 (1987), 2099-2101. %Y A193175 Cf. A193176, A193179, A005848. %K A193175 nonn,fini,full %O A193175 1,1 %A A193175 _N. J. A. Sloane_, Jul 17 2011