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 A249615 #11 Nov 28 2014 22:18:49
%S A249615 0,1,1,1,1,1,2,1,2,1,1,2,1,1,1,1,2,2,2,2,1,2,2,2,2,1,2,1,2,2,2,2,1,2,
%T A249615 1,2,1,1,2,2,2,2,1,2,1,2,1,1,2,1,1,1,1,2,2,2,2,2,3,2,3,2,2,3,2,2,2,1,
%U A249615 2,2,2,2,2,3,2,3,2,2,3,2,2,2
%N A249615 Number of non-singleton blocks in the n-th set partition (A231428).
%H A249615 Tilman Piesk, <a href="/A249615/b249615.txt">Table of n, a(n) for n = 0..9999</a>
%H A249615 Tilman Piesk, <a href="https://commons.wikimedia.org/wiki/File:Set_partitions_5;_list.svg">Illustrated list of the first 52 equivalence relations</a>
%H A249615 Tilman Piesk, <a href="https://en.wikiversity.org/wiki/Permutations_and_partitions_in_the_OEIS">Permutations and partitions in the OEIS</a> (Wikiversity)
%e A249615 The 6th set partition has 2 non-singleton blocks {1,4} and {2,3}. So a(6) = 2.
%Y A249615 Cf. A231428, A249616
%K A249615 nonn
%O A249615 0,7
%A A249615 _Tilman Piesk_, Nov 02 2014