a(n) = (1 + a(n-1)*a(n-2))/a(n-3), a(0) = a(1) = a(2) = 1.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =7a(6) =11a(7) =26a(8) =41a(9) =97a(10) =153a(11) =362a(12) =571a(13) =1351a(14) =2131a(15) =5042a(16) =7953a(17) =18817a(18) =29681a(19) =70226a(20) =110771a(21) =262087a(22) =413403a(23) =978122a(24) =1542841a(25) =3650401a(26) =5757961a(27) =13623482a(28) =21489003a(29) =50843527