#include<stdio.h>
int main(void){
  char *s="python3 -c\""
"n,k=map(int,input().split());a=0\n"
"for i in range(1,n+1):\n"
" j=1/n\n"
" while i<k:i*=2;j/=2\n"
" a+=j\n"
"print(a)\n"
"\"";
  system(s);
  return 0;
}            