mod = 10**9 + 7
N, M, K = gets.split.map(&:to_i)
ans = 0
com = Rational(1, 1)
for i in 0..K-3
  com *= Rational(N*M-2-i, K-2-i)
end
com = com.to_i%mod
for i in 1..N
  ans += (i * (N-i) * M * M) % mod
end
for i in 1..M
  ans += (i * (M-i) * N * N) % mod
end
p ans * com % mod