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 A242839 #5 May 24 2014 18:25:14
%S A242839 2,0,5,0,14,0,22,24,104,228,518,1272,2621,5986,11836,25396,49077,
%T A242839 100200,192678,381724,730806,1424956,2727666,5271456,10111091,
%U A242839 19503830,37551786,72600610,140531739,273027876,531953163,1040051736,2040532257,4017104634,7935847124
%N A242839 Number of compositions of n with difference -2 between the number of odd parts and the number of even parts, both counted without multiplicity.
%H A242839 Alois P. Heinz, <a href="/A242839/b242839.txt">Table of n, a(n) for n = 6..500</a>
%e A242839 a(6) = 2: [2,4], [4,2].
%e A242839 a(8) = 5: [2,2,4], [2,4,2], [4,2,2], [2,6], [6,2].
%e A242839 a(13) = 24 = 4!: all permutations of {1,2,4,6}.
%Y A242839 Column k=-2 of A242626.
%K A242839 nonn
%O A242839 6,1
%A A242839 _Alois P. Heinz_, May 23 2014