137127810959domain: NAppears in sequencesNumber of permutations of 3 copies of 1..n avoiding adjacent step pattern up, up, up, up, up.at n=6A177615Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where T(n,k) = Sum_{j=0..n} (-1)^(n-j) * multinomial(n+(k-1)*j; n-j, {j}^k).at n=48A336169