Number of compositions of n into parts 2 and 3 with at least one 2 and one 3.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =2a(6) =0a(7) =3a(8) =3a(9) =4a(10) =6a(11) =9a(12) =10a(13) =16a(14) =20a(15) =27a(16) =36a(17) =49a(18) =63a(19) =86a(20) =113a(21) =150a(22) =199a(23) =265a(24) =349a(25) =465a(26) =615a(27) =815a(28) =1080a(29) =1432