a(n) = a(n-1)*a(n-3) - 1, starting with a(0)=a(1)=a(2)=2.

A121256

a(n) = a(n-1)*a(n-3) - 1, starting with a(0)=a(1)=a(2)=2.

Terms

    a(0) =2a(1) =2a(2) =2a(3) =3a(4) =5a(5) =9a(6) =26a(7) =129a(8) =1160a(9) =30159a(10) =3890510a(11) =4512991599

External references