Number of compositions of n with difference -2 between the number of odd parts and the number of even parts, both counted without multiplicity.

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.

Terms

    a(0) =2a(1) =0a(2) =5a(3) =0a(4) =14a(5) =0a(6) =22a(7) =24a(8) =104a(9) =228a(10) =518a(11) =1272a(12) =2621a(13) =5986a(14) =11836a(15) =25396a(16) =49077a(17) =100200a(18) =192678a(19) =381724a(20) =730806a(21) =1424956a(22) =2727666a(23) =5271456a(24) =10111091a(25) =19503830a(26) =37551786a(27) =72600610a(28) =140531739a(29) =273027876

External references