a(n)=(2^(2^n) + 3^(2^n) + 5^(2^n))/19.

A132396

a(n)=(2^(2^n) + 3^(2^n) + 5^(2^n))/19.

Terms

    a(0) =2a(1) =38a(2) =20918a(3) =8033210678

External references