n,l=gets.split.map &:to_i
k=l/(n-1)
a=Array.new(k+1,1)
for i in 2..2240;if a[i]then for j in 2..k/i;a[i*j]=nil end;end;end
s=0
for i in 2..k;if a[i]then s+=l-(n-1)*i+1 end;end
puts s