#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int INF = (int) 1e9 + 1e6 + 123;
const ll LINF = (ll) 1e18 + 1e9 + 123;
#define rep(i, s, t) for (auto i = (s); i < (t); ++(i))
#define per(i, s, t) for (auto i = (s); i >= (t); --(i))
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define mp make_pair
#define pb push_back
bool mini(auto &x, const auto &y) {
if (y < x) {
x = y;
return 1;
}
return 0;
}
bool maxi(auto &x, const auto &y) {
if (y > x) {
x = y;
return 1;
}
return 0;
}
void run();
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
run();
return 0;
}
const ll MOD = (ll) 1e9 + 7;
ll power(ll x, ll y) {
if (y == 0) {
return 1;
}
if (y % 2 == 0) {
ll t = power(x, y / 2);
return t * t % MOD;
} else {
return power(x, y - 1) * x % MOD;
}
}
const int N = 3003;
int H, W;
ll f[N];
ll fact[N], rfact[N];
ll cnk(int n, int k) {
return fact[n] * rfact[n - k] % MOD * rfact[k] % MOD;
}
ll calc2(int w, int h) {
if ((w + h) % 3 != 0) {
return 0;
}
int x = w - (w + h) / 3;
int y = (w + h) / 3 - x;
if (x < 0 || y < 0) {
return 0;
}
ll res = cnk(w, y) * cnk(h, x) % MOD;
res = res * f[x] % MOD;
res = res * f[y] % MOD;
return res;
}
ll calc1(int w, int h) {
if (w < h) {
swap(w, h);
}
return (cnk(w, h) * fact[h] % MOD * (power(5, h) + MOD - 1) % MOD + 1) % MOD;
}
void run() {
f[0] = 1;
rep(i, 1, N) {
f[i] = i * 1LL * (2 * i - 1) * f[i - 1] % MOD;
}
fact[0] = 1;
rep(i, 1, N) {
fact[i] = fact[i - 1] * i % MOD;
}
rep(i, 0, N) {
rfact[i] = power(fact[i], MOD - 2);
}
ll ans = MOD - 1;
cin >> H >> W;
rep(h, 0, H + 1) {
rep(w, 0, W + 1) {
ll cur = calc2(w, h) * calc1(W - w, H - h) % MOD;
ans = (ans + cur) % MOD;
}
}
cout << ans << "\n";
}
