local n, l = io.read("*n", "*n")
local maxdiff = math.floor(l / (n - 1))

local function getprimes(x)
  local primes = {}
  local allnums = {}
  for i = 1, x do allnums[i] = true end
  for i = 2, x do
    if(allnums[i]) then
      table.insert(primes, i)
      local lim = math.floor(x / i)
      for j = 2, lim do
        allnums[j * i] = false
      end
    end
  end
  return primes
end

local primes = getprimes(maxdiff)

local cnt = 0
for i = 1, #primes do
  local p = primes[i]
  cnt = cnt + (l - p * (n - 1) + 1)
end
print(cnt)