2582128domain: NAppears in sequencesConsider the least number n such that n divided by pi(n) rounded is greater than any previous n; a(n) is the denominator of n/pi(n).at n=15A107614Number of solutions to 1 +- 3 +- 6 +- ... +- n*(n+1)/2 == 0 mod n.at n=25A300307