class ModCombination
  attr_reader :fac, :inv, :finv, :mod

  MOD = 10 ** 9 + 7

  def initialize(n, mod: MOD)
    @mod = mod
    @fac = [1, 1]
    @inv = [1, 1]
    @finv = [1, 1]

    (2..n).each do |i|
      @fac[i] = fac[i - 1] * i % mod
      @inv[i] = mod - inv[mod % i] * (mod / i) % mod
      @finv[i] = finv[i - 1] * inv[i] % mod
    end
  end

  def combination(n, k)
    return 0 if n < k
    return 0 if n < 0 || k < 0

    fac[n] * (finv[k] * finv[n - k] % mod) % mod
  end
end

N, M, K = gets.split.map(&:to_i)
MOD = 10 ** 9 + 7

ans = 0

(1...N).each do |d|
  ans += d * (N - d) * M ** 2 % MOD
end

(1...M).each do |d|
  ans += d * (M - d) * N ** 2 % MOD
end

mc = ModCombination.new(N * M)
puts mc.combination(N * M - 2, K - 2) * ans % MOD
