132609domain: NAppears in sequencesMiddle of three consecutive semiprimes with common prime factor = 3.at n=2A131409a(n) = 7^n + 5^n - 3^n + 2^n.at n=6A135166Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0100-1100-0111-0001 pattern in any orientation.at n=11A147268