Number of integer compositions of n into parts not covering an interval of positive integers.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =2a(5) =5a(6) =11a(7) =25a(8) =57a(9) =115a(10) =236a(11) =482a(12) =978a(13) =1986a(14) =4003a(15) =8033a(16) =16150a(17) =32402a(18) =64943a(19) =130207a(20) =260805a(21) =522123a(22) =1045168a(23) =2091722a(24) =4185431a(25) =8374100a(26) =16753538a(27) =33515122a(28) =67042865a(29) =134106640