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 A271467 #10 Apr 10 2016 17:55:28 %S A271467 0,1,10,149,3149,88772,3195161,142084077,7611839904,481614364251, %T A271467 35417157810681,2987457716884346,285867917955683723, %U A271467 30741794345071162069,3685435185993122202106,489101076818110701758097,71414666988339306082779537,11410190978037926887950636172 %N A271467 Number of set partitions of [2n] such that n is the largest element of the last block. %C A271467 Each set partition is written as a sequence of blocks, ordered by the smallest elements in the blocks. %H A271467 Alois P. Heinz, <a href="/A271467/b271467.txt">Table of n, a(n) for n = 1..200</a> %H A271467 Wikipedia, <a href="https://en.wikipedia.org/wiki/Partition_of_a_set">Partition of a set</a> %F A271467 a(n) = A271466(2n,n). %e A271467 a(2) = 1: 134|2. %e A271467 a(3) = 10: 12456|3, 1456|23, 1456|2|3, 145|26|3, 146|25|3, 14|256|3, 156|24|3, 15|246|3, 16|245|3, 1|2456|3. %Y A271467 Cf. A271466. %K A271467 nonn %O A271467 1,3 %A A271467 _Alois P. Heinz_, Apr 08 2016