require "prime"
MOD = 1000000007

def nCk(n,k)
	return fact(n)*mypow(fact(k),MOD-2)%MOD*mypow(fact(n-k),MOD-2)%MOD
end

def mypow(a,m)
	return a**m % MOD if m < 4
	c, res = a, 1
	while(m>0);res = res * c % MOD if m.odd?;c, m = c * c % MOD, m >> 1;end
	return res
end

def fact(n)
	res = 1
	Prime.each(n) do |pr|
		m, q, e = n, pr, 0
		e, q = e+m/q, q*pr while q <= m
		res = res *  mypow(pr, e) % MOD
	end
	return res
end

def f(x)
	return (x**3-x)/6%MOD
end

N, M, K = gets.split.map(&:to_i)
puts (N * N * f(M) + M * M * f(N)) % MOD * nCk(N*M-2, K-2) % MOD
