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

A358495

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

Terms

    a(0) =1a(1) =2a(2) =1a(3) =2a(4) =17a(5) =506a(6) =48772a(7) =13681602a(8) =12287555282

External references