1906501

Appears in sequences

• T(n,k) = Number of (n+k-1) X (n+k-1) binary arrays with k 1s in every row and column with rows and columns in lexicographically nondecreasing order.at n=52A227061
• Number of n X n binary matrices with exactly 3 ones in each row and column, and with rows and columns in lexicographically nondecreasing order.at n=9A229162