n, l = gets.split.map(&:to_i)

pmax = l / (n-1)

p = []
not_prime = []
2.upto(pmax) do |i|
  next if not_prime[i]

  p << i
  (i*2).step(pmax, i) do |j|
    not_prime[j] = true
  end
end

c = 0
p.each do |i|
  c += l - ((n-1) * i) + 1
end
puts c