54162domain: NAppears in sequencesCoordination sequence for 4-dimensional RR-centered di-isohexagonal orthogonal lattice.at n=17A008528a(n) = 121*n^2 - 204*n + 86.at n=21A157440Numbers k such that the sum of the divisors of k and the sum of the distinct prime divisors of k are both a square.at n=38A194196