18532800domain: NAppears in sequencesn*(n+1)^2*(n+2)*(n+3)^2*(n+4).at n=9A057666Table read by ascending antidiagonals: T(n, k) is the maximum number of quasi k-gons that are not k-gons in a finite projective plane of order n, with k >= 3.at n=13A342307Expansion of e.g.f. exp( Sum_{k>=0} x^(5*k+2) / (5*k+2) ).at n=13A365972