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 A307346 #12 Apr 24 2019 11:47:49 %S A307346 1,1,3,10,36,138,553,2288,9699,41908 %N A307346 Number of uniquely sorted permutations of [2n+1] that avoid the patterns 231 and 4123. %H A307346 C. Defant, <a href="https://arxiv.org/abs/1904.02627">Catalan intervals and uniquely sorted permutations</a>, arXiv:1904.02627 [math.CO], 2019. %e A307346 The 3 uniquely sorted permutations of [7] that avoid 231 and 4123 are 2164357, 2143657, and 4321567. %Y A307346 Cf. A180874. %K A307346 nonn,more %O A307346 0,3 %A A307346 _Colin Defant_, Apr 03 2019