159975domain: NAppears in sequencesNumbers k such that Sum_{d divides k} sigma(d)/phi(d) is an integer.at n=35A068991a(n) = 625*n^2 - 25.at n=15A157918a(n) = 256*n^2 - n.at n=24A158010Composites whose prime factorization in base 7 is an anagram of the number in base 7.at n=11A260051