136986domain: NAppears in sequencesNumber of nonempty subsets of {1,2,...,n} in which exactly 1/3 of the elements are <= sqrt(n).at n=21A048094Numbers k such that the fractional part of e^k is less than 1/k.at n=9A153702Numbers k such that k - 13, k + 1, k + 5, k + 7, and k + 13 are all prime.at n=17A281937