Number of compositions of n into distinct parts with exactly two descents.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =15a(5) =16a(6) =29a(7) =41a(8) =65a(9) =144a(10) =179a(11) =269a(12) =382a(13) =549a(14) =739a(15) =1286a(16) =1564a(17) =2254a(18) =2978a(19) =4124a(20) =5304a(21) =7264a(22) =10157a(23) =12941a(24) =17027a(25) =22194a(26) =28663a(27) =36884a(28) =47306a(29) =59837