Half the number of compositions of n into exactly two different parts with equal multiplicities.

Terms

a(0) =1a(1) =1a(2) =2a(3) =5a(4) =3a(5) =6a(6) =14a(7) =10a(8) =5a(9) =56a(10) =6a(11) =15a(12) =153a(13) =51a(14) =8a(15) =502a(16) =9a(17) =217a(18) =1756a(19) =25a(20) =11a(21) =7023a(22) =264a(23) =30a(24) =24363a(25) =1852a(26) =14a(27) =93629a(28) =15a(29) =6576