# coding: utf-8
import array, bisect, collections, heapq, itertools, math, random, re, string, sys, time
sys.setrecursionlimit(10 ** 7)
inf = 10 ** 20
mod = 10 ** 9 + 7

def II(): return int(input())
def ILI(): return list(map(int, input().split()))
def IAI(LINE): return [ILI() for __ in range(LINE)]
def IDI(): return {key: value for key, value in ILI()}


def make_prime_list(num):
    if num < 2:
        return []

    # 0のものは素数じゃないとする
    prime_list = [i for i in range(num + 1)]
    prime_list[1] = 0   # 1は素数ではない
    num_sqrt = math.sqrt(num)

    for prime in prime_list:
        if prime == 0:
            continue
        if prime > num_sqrt:
            break

        for non_prime in range(2 * prime, num, prime):
            prime_list[non_prime] = 0

    return [prime for prime in prime_list if prime != 0]


def search_divisor_num_1(num):
    if num < 0:
        return None
    elif num == 1:
        return 1
    else:
        num_sqrt = math.floor(math.sqrt(num))
        prime_list = make_prime_list(num_sqrt)

        divisor_num = 1
        for prime in prime_list:
            count = 1
            while num % prime == 0:
                num //= prime
                count += 1
            divisor_num *= count

        if num != 1:
            divisor_num *= 2

        return divisor_num


def solve(N, p):
    ans = 0
    for n in range(2, N + 1):
        ans += (1 - p) ** (search_divisor_num_1(n) - 2)
    return float(ans)


def main():
    N, p = input().split()
    print(solve(N, p))


if __name__ == "__main__":
    main()