## subroutines

def fact(n)
  f = 1
  for k in (2..n)
    f *= k
  end
  f
end

### main

n, m, r = gets.strip.split(' ').map{|s| s.to_i}

# n+r-mn-1 C r-mn = (n-1+r-mn)! / (r-mn)! / (n-1)!

ans = fact(n + r - m * n - 1) / fact(n - 1) / fact(r - m * n)
puts ans