3418800domain: NAppears in sequencesa(n) = (-1)^n * Sum_{2*m + 1 | 2*n + 1} (-1)^m (2*m + 1)^4.at n=21A204342Numbers k such that floor(k^(1/m)) divides k for all integers m >= 1.at n=53A261205Even positive numbers that are one less than the square of a perfect power.at n=25A389955