44945domain: NAppears in sequencesa(n) = 81*n^2 - 72*n + 17.at n=24A154277Numbers of the form m^2 + 1 that can be expressed in more than one way as j^2 + k^2 with j > k > 1 and gcd(j,k) = 1.at n=27A300166Number of maximal irredundant sets in the n-double cone graph.at n=13A392237