N, M, K = gets.split.map(&:to_i)
MOD = 1E9.to_i + 7

def mpow(x, n)
  ret = 1
  while n > 0
    if n.even?
      x = x * x % MOD
      n >>= 1
    else
      ret = ret * x % MOD
      n -= 1
    end
  end
  ret
end

def comb(n, k)
  k = [k, n - k].min
  (n - k + 1 .. n).inject(1){|p, q| p*q % MOD} * mpow((1 .. k).inject(1){|p, q| p*q % MOD}, MOD - 2)
end

def f(x, y)
  x*(x-1)*(x+1)*y*y / 6 * comb(x*y - 2, K - 2)
end

puts (f(N, M) + f(M, N)) % MOD