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 A275071 #7 Jul 15 2016 16:53:44 %S A275071 1,1,1,1,1,2,4,8,16,40,100,250,625,1875,5625,16875,50625,175500, %T A275071 608400,2109120,7311616,28543424,111429136,435002204,1698181681, %U A275071 7336479479,31695036961,136928804999,591559418641,2792538190620,13182563408400,62230116888000 %N A275071 Number of set partitions of [n] such that i-j is a multiple of four for all i,j belonging to the same block. %H A275071 Alois P. Heinz, <a href="/A275071/b275071.txt">Table of n, a(n) for n = 0..739</a> %H A275071 Wikipedia, <a href="https://en.wikipedia.org/wiki/Partition_of_a_set">Partition of a set</a> %F A275071 a(n) = Product_{i=0..3} A000110(floor((n+i)/4)). %e A275071 a(9) = 40: 159|26|37|48, 15|26|37|48|9, 159|26|37|4|8, 15|26|37|4|8|9, 159|26|3|48|7, 15|26|3|48|7|9, 159|26|3|4|7|8, 15|26|3|4|7|8|9, 159|2|37|48|6, 15|2|37|48|6|9, 159|2|37|4|6|8, 15|2|37|4|6|8|9, 159|2|3|48|6|7, 15|2|3|48|6|7|9, 159|2|3|4|6|7|8, 15|2|3|4|6|7|8|9, 19|26|37|48|5, 1|26|37|48|59, 1|26|37|48|5|9, 19|26|37|4|5|8, 1|26|37|4|59|8, 1|26|37|4|5|8|9, 19|26|3|48|5|7, 1|26|3|48|59|7, 1|26|3|48|5|7|9, 19|26|3|4|5|7|8, 1|26|3|4|59|7|8, 1|26|3|4|5|7|8|9, 19|2|37|48|5|6, 1|2|37|48|59|6, 1|2|37|48|5|6|9, 19|2|37|4|5|6|8, 1|2|37|4|59|6|8, 1|2|37|4|5|6|8|9, 19|2|3|48|5|6|7, 1|2|3|48|59|6|7, 1|2|3|48|5|6|7|9, 19|2|3|4|5|6|7|8, 1|2|3|4|59|6|7|8, 1|2|3|4|5|6|7|8|9. %Y A275071 Column k=4 of A275069. %Y A275071 Cf. A000110. %K A275071 nonn %O A275071 0,6 %A A275071 _Alois P. Heinz_, Jul 15 2016