24243520

Appears in sequences

• Number of {2,3}-regular graphs; i.e., labeled simple graphs (no multi-edges or loops) on n vertices, each of degree 2 or 3.at n=9A110040
• Number of n X n symmetric binary matrices with all row sums 6.at n=3A139673
• Number of 9 X 9 arrays of squares of integers, symmetric about main diagonal, with all rows summing to n.at n=3A156398
• T(n,k)=Number of (n*k)Xk binary arrays with nonzero rows in decreasing order, no more than 2 ones in any row and exactly n ones in every column.at n=57A188448
• Triangle read by rows: T(n,k) is the number of n X n symmetric binary matrices with k ones in every row and column.at n=48A333157
• Triangle read by rows: T(n,k) is the number of n X n symmetric binary matrices with k ones in every row and column.at n=51A333157