import math

tmp = input().split(" ")
N = int(tmp[0])
p = float(tmp[1])

cand = [i for i in range(3, N+1, 2)]
primes = [2]
while len(cand) > 0:
    primes.append(cand[0])
    if primes[-1] * primes[-1] > N:
        break
    cand = [i for i in cand[1:] if i % primes[-1] != 0]
primes = set(primes)
count = 0
memo = {}
for i in range(2, N+1):
    if i in primes:
        count += 1.0
        memo[i] = 1
    else:
        cnt = 0
        for j in range(2,i):
            if i % j == 0:
                cnt += 1
                if memo.get(i//j,0) != 0:
                    cnt += memo[i//j]
                    break
        memo[i] = cnt
        count += (1.0-p) ** cnt
print(count)