a(n) = denominator((2^n*(n!)^2/(1+2*n)!)^2).

A392619

a(n) = denominator((2^n*(n!)^2/(1+2*n)!)^2).

Terms

    a(0) =1a(1) =9a(2) =225a(3) =1225a(4) =99225a(5) =480249a(6) =9018009a(7) =41409225a(8) =11967266025a(9) =53335593025a(10) =940839860961

External references