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 A202694 #16 Jun 04 2020 01:54:01 %S A202694 1,2,3,5,3,0,46,51,54,54,205,159,108,54,0 %N A202694 The third of three triangles counting 3-colored alternating permutations by their last value. %H A202694 M. Josuat-Verges, J.-C. Novelli and J.-Y. Thibon, <a href="http://arxiv.org/abs/1110.5272">The algebraic combinatorics of snakes</a>, arXiv preprint arXiv:1110.5272 [math.CO], 2011. %e A202694 Triangle begins: %e A202694 1 %e A202694 2 3 %e A202694 5 3 0 %e A202694 46 51 54 54 %e A202694 205 159 108 54 0 %e A202694 ... %Y A202694 See A202692 for further information. %Y A202694 Cf. A202693. %K A202694 nonn,tabl,more %O A202694 1,2 %A A202694 _N. J. A. Sloane_, Dec 23 2011