#include <bits/stdc++.h>
using namespace std;
constexpr int MOD = 1e9 + 7;
int binpow(int n, int k) {
int ans = 1;
while (k) {
if (k & 1) {
ans = ans * 1LL * n % MOD;
}
n = n * 1LL * n % MOD;
k >>= 1;
}
return ans;
}
void solve() {
int n, m;
cin >> n >> m;
vector<int> sz(m);
for (int i = 0; i < n * 2; ++i) {
sz[i % m]++;
}
vector<int> f(n * 2 + 1), _f(n * 2 + 1);
f[0] = _f[0] = 1;
for (int i = 1; i <= n * 2; ++i) {
f[i] = f[i - 1] * 1LL * i % MOD;
_f[i] = binpow(f[i], MOD - 2);
}
auto c = [&](int n, int k) -> int {
return f[n] * 1LL * _f[k] % MOD * _f[n - k] % MOD;
};
vector<int> dp(n + 1);
vector<vector<int>> dp_nw(m + 1, vector<int>(n + 1));
dp_nw[0][0] = 1;
for (int i = 0; i < m; ++i) {
for (int cnt_prv = 0; cnt_prv <= n; ++cnt_prv) {
for (int add = 0; cnt_prv + add <= n && add * 2 <= sz[i]; ++add) {
dp_nw[i + 1][cnt_prv + add] += dp_nw[i][cnt_prv] * 1LL * c(sz[i], add * 2) % MOD * f[add * 2] % MOD * c(n - cnt_prv, add) % MOD;
if (dp_nw[i + 1][cnt_prv + add] >= MOD) {
dp_nw[i + 1][cnt_prv + add] -= MOD;
}
}
}
}
for (int cnt = n; cnt >= 0; --cnt) {
dp[cnt] = dp_nw[m][cnt];
dp[cnt] = dp[cnt] * 1LL * f[n * 2 - cnt * 2] % MOD;
for (int cnt2 = cnt + 1; cnt2 <= n; ++cnt2) {
dp[cnt] = (dp[cnt] - (dp[cnt2] * 1LL * c(cnt2, cnt) % MOD) + MOD) % MOD;
}
}
cout << dp[0] << '\n';
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int t = 1;
// cin >> t;
while (t--) {
solve();
}
return 0;
}
