#include <iostream>
#define int long long
using namespace std;
const int NMAX = 2000;
const int MOD = 1e9 + 7;
int dp[NMAX + 1][NMAX + 1];
int sz[NMAX + 1];
int s[NMAX + 1];
int comb[NMAX + 1][NMAX + 1];
int fact[NMAX + 1];
int C(int n, int k){
if(n < 0 || k < 0 || k > n){
return 0;
}
return comb[n][k];
}
int f(int s, int j){
if((s - j) % 2 == 1){
return -1;
}
return j + ((s - j) / 2);
}
signed main(){
comb[0][0] = 1;
for(int i = 1; i <= NMAX; i++){
comb[i][0] = 1;
for(int j = 1; j <= NMAX; j++){
comb[i][j] = (comb[i - 1][j] + comb[i - 1][j - 1]) % MOD;
}
}
int n, m;
cin >> n >> m;
n *= 2;
for(int i = 1; i <= m; i++){
for(int j = i; j <= n; j += m){
sz[i]++;
}
s[i] = s[i - 1] + sz[i];
}
n /= 2;
dp[1][sz[1]] = C(n, sz[1]);
for(int i = 1; i <= m - 1; i++){
for(int j = 0; j <= n; j++){
for(int k = 0; k <= min(j, sz[i + 1]); k++){
int newJ = j - k + (sz[i + 1] - k);
if(newJ > n){
continue;
}
int r = n - f(s[i] + k, j - k);
if(r == -1){
continue;
}
(dp[i + 1][newJ] += ((dp[i][j] * C(j, k)) % MOD * C(r, sz[i + 1] - k)) % MOD) %= MOD;
}
}
}
int ans = dp[m][0];
fact[0] = 1;
for(int i = 1; i <= 2 * n; i++){
(fact[i] = fact[i - 1] * i) %= MOD;
}
int pw = 1;
for(int i = 1; i <= n; i++){
(pw *= 2) %= MOD;
}
ans = (ans * pw) % MOD;
for(int i = 1; i <= m; i++){
(ans *= fact[sz[i]]) %= MOD;
}
cout << ans <<'\n';
return 0;
}
