60826domain: NAppears in sequencesa(n) = (2*n - 1)*(11*n^2 - 11*n + 6)/6.at n=25A063492Triangle read by rows: T(n,k) (1 <= k <= n) = number of ascendingly generated semigroups of order n with k generators.at n=17A256411Length of row n of the array in A274183.at n=27A274184