a(n+5) = (a(n+4)*a(n+1) + 2*a(n+3)*a(n+2))/a(n).

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =3a(6) =5a(7) =11a(8) =41a(9) =233a(10) =689a(11) =5337a(12) =49081a(13) =458299a(14) =3603685a(15) =93208147a(16) =1476087601a(17) =27470407569a(18) =816413467841