a(n) = prime(n) * 3^prime(n) - 1.

A100688

a(n) = prime(n) * 3^prime(n) - 1.

Terms

    a(0) =17a(1) =80a(2) =1214a(3) =15308a(4) =1948616a(5) =20726198a(6) =2195382770a(7) =22082967872

External references