Row sums of triangle A118180: a(n) = Sum_{k=0..n} (3^k)^(n-k) for n>=0.

A118181

Row sums of triangle A118180: a(n) = Sum_{k=0..n} (3^k)^(n-k) for n>=0.

Terms

    a(0) =1a(1) =2a(2) =5a(3) =20a(4) =137a(5) =1622a(6) =33293a(7) =1182440a(8) =72811793a(9) =7757988842

External references