a(n) = (2*n)! / CatalanNumber(n - 1) for n >= 1 and a(0) = 1.

A344057

a(n) = (2*n)! / CatalanNumber(n - 1) for n >= 1 and a(0) = 1.

Terms

    a(0) =1a(1) =2a(2) =24a(3) =360a(4) =8064a(5) =259200a(6) =11404800a(7) =660441600a(8) =48771072000

External references