N,K = map(int, input().split())
a = 0
for i in range(1,N+1):
  c = 0
  while i<K:
    c+=1
    i*=2
  a += (0.5**c)/N
 
print(a) N,K = map(int, input().split()) N map(int, input().split()) map int input().split() ().split () input split K a = 0 a 0 for i in range(1,N+1):
  c = 0
  while i<K:
    c+=1
    i*=2
  a += (0.5**c)/N
  i range(1,N+1) range 1 N+1 N 1 c = 0 c 0 while i<K:
    c+=1
    i*=2
   i<K i K c+=1 c 1 i*=2 i 2 a += (0.5**c)/N a (0.5**c)/N 0.5**c 0.5 c N print(a) print a K = map(int, input().split()) map(int, input().split()) K c = 0 0 c i*=2 2 i c+=1 1 c N,K = map(int, input().split()) map(int, input().split()) N a = 0 0 a a += (0.5**c)/N (0.5**c)/N a
N,K = map(int, input().split())
a = 0
for i in range(1,N+1):
  c = 0
  while i<K:
    c+=1
    i*=2
  a += (0.5**c)/N
 
print(a)