#include <bits/stdc++.h>
using namespace std;
const int MOD = 1000000007;
typedef long long ll;
int add(int a, int b){
return (a+b)%MOD;
}
int mul(int a, int b){
return ((ll)a*b)%MOD;
}
int pw(int a, int b){
if(b == 0) return 1;
int res = pw(a, b/2);
res = mul(res, res);
if(b%2) res = mul(res, a);
return res;
}
int inv[3005];
int fact[3005];
int bin(int n, int k){
if(n < 0 || k < 0 || n < k) return 0;
int res = fact[n];
res = mul(res, inv[n-k]);
res = mul(res, inv[k]);
return res;
}
int brackets[3005][3005];
int main(){
ios_base::sync_with_stdio(false);
fact[0] = inv[0] = 1;
for(int i=1; i<=3000; i++){
fact[i] = mul(fact[i-1], i);
inv[i] = pw(fact[i], MOD-2);
}
brackets[0][0] = 1;
for(int i=0; i<3000; i++){
for(int j=0; j<=i; j++){
brackets[i+1][j+1] = add(brackets[i+1][j+1], brackets[i][j]);
if(j) brackets[i+1][j-1] = add(brackets[i+1][j-1], mul(j, brackets[i][j]));
}
}
int h, w;
cin >> h >> w;
int res = 0;
//cout << brackets[4][0] << "eee";
for(int i=0; i<=h && 2*i<=w; i++){
for(int j=0; j+2*i<=w && 2*j+i<=h; j++){
/// i = broj hor. parova
/// j = broj ver. parova
int tren = 1;
/// hor. parovi
tren = mul(tren, bin(h, i));
tren = mul(tren, fact[i]);
tren = mul(tren, bin(w, 2*i));
tren = mul(tren, brackets[2*i][0]);
/// ver. parovi
/// ostalo je h-i redova i w-2*i kolona
tren = mul(tren, bin(w-2*i, j));
tren = mul(tren, fact[j]);
tren = mul(tren, bin(h-i, 2*j));
tren = mul(tren, brackets[2*j][0]);
/// sami
/// ostalo je h-i-2*j redova i w-2*i-j kolona
int h1 = h-i-2*j, w1 = w-2*i-j;
int g = 0;
tren = mul(tren, fact[w1]);
tren = mul(tren, fact[h1]);
for(int k=0; k<=min(h1, w1); k++){
if(i+j+k == 0) continue;
int t2 = 1;
t2 = mul(t2, pw(4, k));
t2 = mul(t2, inv[k]);
t2 = mul(t2, inv[h1-k]);
t2 = mul(t2, inv[w1-k]);
g = add(g, t2);
}
res = add(res, mul(tren, g));
}
}
cout << res;
return 0;
}
