a(n) = Sum_{k=0..n} binomial(5*n+3,5*k).

A345457

a(n) = Sum_{k=0..n} binomial(5*n+3,5*k).

Terms

    a(0) =1a(1) =57a(2) =1574a(3) =53143a(4) =1669801a(5) =53774932a(6) =1717012749a(7) =54986385093

External references