#include <bits/stdc++.h>
using namespace std;
int n, m, k;
long long inv[900010], fac[900010], p[900010], ans;
const long long mod = 1e9 + 7;
inline long long ksm(long long x, long long y) {
  long long res = 1;
  while (y) {
    if (y & 1) res = res * x % mod;
    x = x * x % mod;
    y >>= 1;
  }
  return res;
}
inline long long c(int x, int y) {
  return fac[x] * inv[y] % mod * inv[x - y] % mod;
}
int main() {
  scanf("%d%d%d", &n, &m, &k);
  p[0] = 1;
  fac[0] = 1;
  inv[0] = 1;
  for (int i = 1; i <= 9e5; ++i) {
    p[i] = p[i - 1] * 3 % mod;
    fac[i] = fac[i - 1] * i % mod;
  }
  inv[900000] = ksm(fac[900000], mod - 2);
  for (int i = 9e5 - 1; i >= 1; --i) inv[i] = inv[i + 1] * (i + 1) % mod;
  long long x = 1;
  --n;
  for (int i = 0; i <= m + k; ++i) {
    ans = (ans + c(n + i, n) * p[m + k - i] % mod * x) % mod;
    if (i < k)
      x = x * 2 % mod;
    else if (i < m)
      x = (x * 2 - c(i, k) + mod) % mod;
    else
      x = (x * 2 - c(i, k) - c(i, m) + mod + mod) % mod;
  }
  printf("%lld\n", ans);
  return 0;
}
