G.f. A(x) satisfies A(x) = 1 / ((1 - x) * (1 - x * A(x^4))).

Terms

a(0) =1a(1) =2a(2) =3a(3) =4a(4) =5a(5) =8a(6) =13a(7) =20a(8) =29a(9) =43a(10) =66a(11) =102a(12) =155a(13) =233a(14) =352a(15) =536a(16) =817a(17) =1240a(18) =1878a(19) =2848a(20) =4327a(21) =6576a(22) =9984a(23) =15150a(24) =22995a(25) =34919a(26) =53029a(27) =80513a(28) =122224a(29) =185556