27694domain: NAppears in sequencesNumbers n such that sigma(2*phi(n)) = 2*sigma(n).at n=14A137733Expansion of 1/(x^k*(1-x-3*x^(k+1))) for k=7.at n=30A143458Number of distinct values of the sum of 4 products of three 0..n integers.at n=19A225261