import std.algorithm, std.array, std.container, std.range, std.bitmanip;
import std.numeric, std.math, std.bigint, std.random, core.bitop;
import std.string, std.regex, std.conv, std.stdio, std.typecons;

void main()
{
  auto rd = readln.split;
  auto n = rd[0].to!int, p = rd[1].to!real;

  auto memo = new int[](n + 1);
  foreach (i; 2..n + 1)
    foreach (j; iota(i * 2, n + 1, i))
      memo[j] += 1;

  auto ri = new real[](n + 1);
  foreach (i; 2..n + 1) {
    auto d = memo[i];
    if (d == 0)
      ri[i] = 1;
    else
      ri[i] = (1 - p) ^^ d;
  }

  writefln("%.7f", ri[2..$].sum);
}