88962domain: NAppears in sequencesNumber of multigraphs with loops on 4 nodes with n edges.at n=16A050532Number of 2 X 2 matrices having all terms in {1,...,n} and determinant d satisfying -n < d < n.at n=29A211070a(n) = 10*binomial(n,5) + 4*binomial(n,3) + n.at n=18A383797