a(n) = Sum_{k=0..n} binomial(4n+3,4k).

A090408

a(n) = Sum_{k=0..n} binomial(4n+3,4k).

Terms

    a(0) =1a(1) =36a(2) =496a(3) =8256a(4) =130816a(5) =2098176a(6) =33550336a(7) =536887296a(8) =8589869056a(9) =137439215616

External references