72092domain: NAppears in sequencesNumbers n such that 2 * (1^n + 2^n + 3^n + ... + n^n) is not 0 (mod n), but 2 * (1^d + 2^d + 3^d + ... + d^d) is 0 (mod d) for each other d | n.at n=28A280187Number of length-n quasiperiodic binary strings.at n=30A320434