a(n) = (5^(2*n) + 3*2^(5*n-2))/7.

A386394

a(n) = (5^(2*n) + 3*2^(5*n-2))/7.

Terms

    a(0) =7a(1) =199a(2) =5743a(3) =168151a(4) =4990207a(5) =149920999a(6) =4553331343a(7) =139603087351

External references