a(n) = sqrt( binomial(4n,0) * binomial(4n,1) * ... * binomial(4n,2n-1) ).

A165975

a(n) = sqrt( binomial(4n,0) * binomial(4n,1) * ... * binomial(4n,2n-1) ).

Terms

    a(0) =1a(1) =2a(2) =112a(3) =261360a(4) =27983155200

External references