762488domain: NAppears in sequencesa(n) is the number of odd numbers k in range [2^n, (2^(n+1))-1] such that all terms in finite sequence [k, floor(k/2), floor(k/4), floor(k/8), ..., 1] are squarefree.at n=46A293441Least number k which is not a divisor of n such that k^2 - n is a nonsquare powerful number.at n=18A309246