25993domain: NAppears in sequencesa(n) = 14*n^3 - 30*n^2 + 24*n - 7.at n=12A155883a(n) = 18*n^2 + 1.at n=37A157889a(n) = 72*n^2 + 1.at n=19A158740Number of 0..n arrays x(0..3) of 4 elements with nondecreasing average value.at n=19A200764Nonsemiprimes in A306097 = A121707 \ A267999.at n=36A321488