238773109domain: NAppears in sequencesNumber of tri-coverings of a set.at n=7A165434Number of (7*n) X 7 binary arrays with rows in nonincreasing order and n ones in every column.at n=2A188391T(n,k) = number of (n*k) X k binary arrays with rows in nonincreasing order and n ones in every column.at n=38A188392