4954521600domain: NAppears in sequencesProducts of the digits of e excluding 0.at n=16A084674a(n) = Product_{1 <= i < j <= n} 2*(i+j-1).at n=4A203516Total number of distinct Hadamard matrices of order 4n.at n=1A206711Total number of distinct Hadamard matrices of order n.at n=7A206712