def fact(n)
  @memo ||= []
  @memo[n] ||= (n==0) ? 1 : (n * fact(n-1)) % MOD;
end

def modpow(x,n)
  ret = 1
  while n > 0
    ret = (ret * x) % MOD if n&1 == 1
    x = (x*x) % MOD
    n >>= 1
  end
  return ret
end

def combin(n,k)
  return (((fact(n) * modpow(fact(n-k),MOD-2)) % MOD) * modpow(fact(k),MOD-2)) % MOD
end

MOD = 10**9 + 7
n,m,k = gets.split.map(&:to_i)

(n*m).times do |i|
  fact(i)
end

x = [n,m].max
csum = [0]*(x+1)
1.upto(x) do |i|
  csum[i] = (csum[i-1] + i) % MOD
end

sum = 0
n.times do |i|
  m.times do |j|
    sum += (csum[i] * m) % MOD
    sum += (csum[j] * n) % MOD
    sum %= MOD
  end
end

mul = combin(n*m-2,k-2)
p (sum*mul) % MOD
