Compositions: 6th column of A048004.

Terms

a(0) =1a(1) =2a(2) =5a(3) =12a(4) =28a(5) =64a(6) =143a(7) =315a(8) =687a(9) =1485a(10) =3186a(11) =6792a(12) =14401a(13) =30391a(14) =63872a(15) =133751a(16) =279177a(17) =581040a(18) =1206151a(19) =2497895a(20) =5161982a(21) =10646564a(22) =21919161a(23) =45052841a(24) =92461171a(25) =189489255a(26) =387830160a(27) =792810956a(28) =1618840800a(29) =3301999647