a(n) = a(n-1)+a(n-4).

Terms

a(0) =1a(1) =1a(2) =1a(3) =5a(4) =6a(5) =7a(6) =8a(7) =13a(8) =19a(9) =26a(10) =34a(11) =47a(12) =66a(13) =92a(14) =126a(15) =173a(16) =239a(17) =331a(18) =457a(19) =630a(20) =869a(21) =1200a(22) =1657a(23) =2287a(24) =3156a(25) =4356a(26) =6013a(27) =8300a(28) =11456a(29) =15812