230832domain: NAppears in sequencesTriangle read by rows: T(n,k) is the number of multigraphs without loops on n labeled nodes with k edges and maximum degree 2.at n=50A095693Permanent of the n-th principal submatrix of A204443.at n=9A204444Permanent of the n-th principal submatrix of A204447.at n=9A204448