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