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%I #6 May 24 2014 18:33:17
%S 2,3,6,11,20,25,41,85,148,355,751,1701,3756,8255,17513,37038,76349,
%T 156618,317591,639142,1279302,2546711,5057675,10010975,19788607,
%U 39058684,77055159,151930328,299600229,590849561,1165782514,2301229945,4545782370,8985884632
%N 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 Alois P. Heinz, <a href="/A242842/b242842.txt">Table of n, a(n) for n = 4..500</a>
%e a(4) = 2: [1,3], [3,1].
%e a(5) = 3: [1,1,3], [1,3,1], [3,1,1].
%e a(6) = 6: [1,1,1,3], [1,1,3,1], [1,3,1,1], [3,1,1,1], [1,5], [5,1].
%Y Column k=2 of A242626.
%K nonn
%O 4,1
%A _Alois P. Heinz_, May 23 2014