8230118400domain: NAppears in sequencesa(n) = n! / A284567(n).at n=18A284568a(n) = n! / A284567(n).at n=19A284568Triangle read by rows: T(n,k) is the coefficient of x^(2*k) in the cycle polynomial of the complete bipartite graph K_{n,n}, 1 <= k <= n.at n=43A291909a(n) is the denominator of Sum_{k=0..n} (-1)^k / (k!)^2.at n=9A354305