a(n) = 4^n + 3 * 18^n.

A334991

a(n) = 4^n + 3 * 18^n.

Terms

    a(0) =4a(1) =58a(2) =988a(3) =17560a(4) =315184a(5) =5669728a(6) =102040768a(7) =1836676480a(8) =33059947264a(9) =595078133248

External references