#include <bits/stdc++.h>
using namespace std;
const long long maxn = 3e3 + 100;
const long long mod = 1e9 + 7;
const long long inf = 1e18;
long long n, m, k, c[maxn][maxn], ans, p[maxn];
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  ;
  p[0] = 1;
  c[0][0] = 1;
  for (long long i = 1; i < maxn; i++) {
    p[i] = (p[i - 1] * 3) % mod;
    c[i][0] = 1;
    for (long long j = 1; j < maxn; j++) {
      c[i][j] = (c[i - 1][j - 1] + c[i - 1][j]);
      if (c[i][j] >= mod) c[i][j] -= mod;
    }
  }
  cin >> n >> m >> k;
  m++;
  k++;
  for (long long i = n; i < maxn; i++) {
    for (long long j = 0; j < m; j++) {
      long long x = i - n - j;
      if (x < 0 || x >= k) continue;
      ans = (ans +
             ((c[i - 1][n - 1] * c[i - n][j]) % mod) * p[n + m + k - i - 2]) %
            mod;
    }
  }
  cout << ans;
  return 0;
}
