import sequtils,strutils,strscans
var
    N : int
    p : float
    s = stdin.readline
    A : array[1000002, float]
    ans : float
discard scanf(s,"$i $f", N, p)
for i in 2..N:
    A[i] = 1
for i in 2..N:
    ans += A[i]
    var j = i * 2
    while j <= N:
        A[j] *= 1 - p
        j += i

echo ans