import sys

readline = sys.stdin.readline
MOD = 10 ** 9 + 7
INF = float('INF')
sys.setrecursionlimit(10 ** 5)


def comb_mod(n, r):
    res = 1
    r = min(n - r, r)

    for i in range(r):
        res *= (n - i)
        res %= MOD
        res *= pow((r - i), MOD - 2, MOD)

    return res


def main():
    n, m, k = list(map(int, readline().split()))

    com = comb_mod(n * m - 2, k - 2)
    x = 0
    y = 0

    for i in range(n):
        right = n - 1 - i
        x += (right + 1) * right // 2
        x %= MOD

    for i in range(m):
        down = m - 1 - i
        y += (down + 1) * down // 2
        y %= MOD

    ans = 0
    ans += m ** 2 * x * com
    ans += n ** 2 * y * com
    ans %= MOD

    print(ans)


if __name__ == '__main__':
    main() import sys sys readline = sys.stdin.readline readline sys.stdin.readline sys.stdin sys stdin readline MOD = 10 ** 9 + 7 MOD 10 ** 9 + 7 10 ** 9 10 9 7 INF = float('INF') INF float('INF') float 'INF' sys.setrecursionlimit(10 ** 5) sys.setrecursionlimit sys setrecursionlimit 10 ** 5 10 5 def comb_mod(n, r):
    res = 1
    r = min(n - r, r)

    for i in range(r):
        res *= (n - i)
        res %= MOD
        res *= pow((r - i), MOD - 2, MOD)

    return res comb_mod res = 1 res 1 r = min(n - r, r) r min(n - r, r) min n - r n r r for i in range(r):
        res *= (n - i)
        res %= MOD
        res *= pow((r - i), MOD - 2, MOD)

     i range(r) range r res *= (n - i) res n - i n i res %= MOD res MOD res *= pow((r - i), MOD - 2, MOD) res pow((r - i), MOD - 2, MOD) pow r - i r i MOD - 2 MOD 2 MOD return res res n n r r def main():
    n, m, k = list(map(int, readline().split()))

    com = comb_mod(n * m - 2, k - 2)
    x = 0
    y = 0

    for i in range(n):
        right = n - 1 - i
        x += (right + 1) * right // 2
        x %= MOD

    for i in range(m):
        down = m - 1 - i
        y += (down + 1) * down // 2
        y %= MOD

    ans = 0
    ans += m ** 2 * x * com
    ans += n ** 2 * y * com
    ans %= MOD

    print(ans) main n, m, k = list(map(int, readline().split())) n list(map(int, readline().split())) list map(int, readline().split()) map int readline().split() ().split () readline split m k com = comb_mod(n * m - 2, k - 2) com comb_mod(n * m - 2, k - 2) comb_mod n * m - 2 n * m n m 2 k - 2 k 2 x = 0 x 0 y = 0 y 0 for i in range(n):
        right = n - 1 - i
        x += (right + 1) * right // 2
        x %= MOD

     i range(n) range n right = n - 1 - i right n - 1 - i n - 1 n 1 i x += (right + 1) * right // 2 x (right + 1) * right // 2 (right + 1) * right right + 1 right 1 right 2 x %= MOD x MOD for i in range(m):
        down = m - 1 - i
        y += (down + 1) * down // 2
        y %= MOD

     i range(m) range m down = m - 1 - i down m - 1 - i m - 1 m 1 i y += (down + 1) * down // 2 y (down + 1) * down // 2 (down + 1) * down down + 1 down 1 down 2 y %= MOD y MOD ans = 0 ans 0 ans += m ** 2 * x * com ans m ** 2 * x * com m ** 2 * x m ** 2 m 2 x com ans += n ** 2 * y * com ans n ** 2 * y * com n ** 2 * y n ** 2 n 2 y com ans %= MOD ans MOD print(ans) print ans if __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main readline = sys.stdin.readline sys.stdin.readline readline MOD = 10 ** 9 + 7 10 ** 9 + 7 MOD def main():
    n, m, k = list(map(int, readline().split()))

    com = comb_mod(n * m - 2, k - 2)
    x = 0
    y = 0

    for i in range(n):
        right = n - 1 - i
        x += (right + 1) * right // 2
        x %= MOD

    for i in range(m):
        down = m - 1 - i
        y += (down + 1) * down // 2
        y %= MOD

    ans = 0
    ans += m ** 2 * x * com
    ans += n ** 2 * y * com
    ans %= MOD

    print(ans) def main():
    n, m, k = list(map(int, readline().split()))

    com = comb_mod(n * m - 2, k - 2)
    x = 0
    y = 0

    for i in range(n):
        right = n - 1 - i
        x += (right + 1) * right // 2
        x %= MOD

    for i in range(m):
        down = m - 1 - i
        y += (down + 1) * down // 2
        y %= MOD

    ans = 0
    ans += m ** 2 * x * com
    ans += n ** 2 * y * com
    ans %= MOD

    print(ans) main INF = float('INF') float('INF') INF def comb_mod(n, r):
    res = 1
    r = min(n - r, r)

    for i in range(r):
        res *= (n - i)
        res %= MOD
        res *= pow((r - i), MOD - 2, MOD)

    return res def comb_mod(n, r):
    res = 1
    r = min(n - r, r)

    for i in range(r):
        res *= (n - i)
        res %= MOD
        res *= pow((r - i), MOD - 2, MOD)

    return res comb_mod
import sys

readline = sys.stdin.readline
MOD = 10 ** 9 + 7
INF = float('INF')
sys.setrecursionlimit(10 ** 5)


def comb_mod(n, r):
    res = 1
    r = min(n - r, r)

    for i in range(r):
        res *= (n - i)
        res %= MOD
        res *= pow((r - i), MOD - 2, MOD)

    return res


def main():
    n, m, k = list(map(int, readline().split()))

    com = comb_mod(n * m - 2, k - 2)
    x = 0
    y = 0

    for i in range(n):
        right = n - 1 - i
        x += (right + 1) * right // 2
        x %= MOD

    for i in range(m):
        down = m - 1 - i
        y += (down + 1) * down // 2
        y %= MOD

    ans = 0
    ans += m ** 2 * x * com
    ans += n ** 2 * y * com
    ans %= MOD

    print(ans)


if __name__ == '__main__':
    main()
