a(n) = Product_{k=1..n} (9*k - 1); 9-factorial numbers.

A049211

a(n) = Product_{k=1..n} (9*k - 1); 9-factorial numbers.

Terms

    a(0) =1a(1) =8a(2) =136a(3) =3536a(4) =123760a(5) =5445440a(6) =288608320a(7) =17893715840

External references