a(n) = 4^n*(Gamma(n+1/4)/Gamma(1/4) + (n-1)!).

A123334

a(n) = 4^n*(Gamma(n+1/4)/Gamma(1/4) + (n-1)!).

Terms

    a(0) =5a(1) =21a(2) =173a(3) =2121a(4) =34521a(5) =700365a(6) =17017605a(7) =481714065a(8) =15566262705a(9) =565382074005

External references