Number of compositions of n where differences between neighboring parts are in {-2,-1,1,2}.

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =4a(5) =5a(6) =11a(7) =14a(8) =18a(9) =36a(10) =49a(11) =66a(12) =118a(13) =169a(14) =238a(15) =401a(16) =586a(17) =846a(18) =1371a(19) =2042a(20) =2998a(21) =4731a(22) =7114a(23) =10566a(24) =16419a(25) =24809a(26) =37118a(27) =57139a(28) =86558a(29) =130151