3786745domain: NAppears in sequencesa(n) = 4*n*a(n-1) + 1 with a(0)=1.at n=6A056545Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of the e.g.f. exp(x)/(1 - k*x).at n=61A320031Triangle read by rows: T(n, k) = n! * 4^k * hypergeom([-k], [-n], 1/4).at n=27A375613