def spp(n):
tong=0
for i in range(1,n):
if n%i==0:
tong += i
return tong

def kiemtra(n):
return spp(n)>n
L=int(input())
R=int(input())
dem=0
for i in range(L,R+1):
if kiemtra(i):
dem=dem+1
print(dem)