Number of weakly unimodal compositions of n with absolute difference of successive parts <= 1.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =6a(5) =10a(6) =14a(7) =21a(8) =27a(9) =40a(10) =52a(11) =70a(12) =92a(13) =124a(14) =156a(15) =206a(16) =264a(17) =335a(18) =425a(19) =539a(20) =673a(21) =847a(22) =1052a(23) =1300a(24) =1611a(25) =1990a(26) =2433a(27) =2977a(28) =3638a(29) =4420