76484389121domain: NAppears in sequencesNumber of multiset permutations of {1, 1, 2, 2, ..., n, n} with no fixed pair (j,j).at n=8A374980T(n,k) is the number of permutations of the multiset {1, 1, 2, 2, ..., n, n} with k occurrences of fixed pairs (j,j), where T(n,k), n >= 2, 0 <= k <= n-2 is a triangle read by rows.at n=21A375220