def main():
    import sys
    N, p = sys.stdin.readline().split()
    N = int(N)
    p = float(p)
    
    # Initialize div_count to count the number of divisors d where 1 < d < k for each k
    div_count = [0] * (N + 1)
    
    for d in range(2, N):
        multiple = 2 * d
        while multiple <= N:
            div_count[multiple] += 1
            multiple += d
    
    # Calculate the sum of expected values
    expected = 0.0
    for k in range(2, N + 1):
        if div_count[k] == 0:
            # It's a prime
            expected += 1.0
        else:
            # Composite, multiply (1 - p) for each divisor
            expected += (1.0 - p) ** div_count[k]
    
    # Print with enough precision
    print("{0:.10f}".format(expected))

if __name__ == "__main__":
    main()