10861066216domain: NAppears in sequencesa(n) = C(2n,n)*C(2n+2,n+1)/(n+2).at n=10A172392Square array read by ascending antidiagonals: T(n,k) = (2*k)!/k! * ( (2*n*k)! * ((2*n+1)*k)! )/( (n*k)!^2 * ((n+1)*k)!^2 ).at n=30A364506