#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll N = 4005, mod = 1e9 + 7;
ll n, m, cnt[N], dp[N][N], comb[N][N], f[N], inv[N], prod[N]; // dp[i][j], ways to choose j pairs of places from the first i cnt of mods of m.
ll pwr(ll a, ll b){
ll res = 1;
for (; b; b/=2, a = (a * a) % mod) if (b & 1) res = (res * a) % mod;
return res;
}
int main(){
f[0] = 1;
for (ll i = 0; i < N; i ++){
if (i) inv[i] = pwr(i, mod - 2);
if (i) f[i] = (f[i - 1] * i) % mod;
comb[i][0] = comb[i][i] = 1;
for (ll j = 1; j < i; j ++)
comb[i][j] = (comb[i - 1][j - 1] + comb[i - 1][j]) % mod;
}
cin >> n >> m;
for (ll i = 1; i <= 2 * n; i ++)
cnt[1 + (i % m)]++;
prod[2] = 1;
for (ll i = 4; i < N; i += 2)
prod[i] = comb[i][2] * prod[i - 2] % mod;
dp[0][0] = 1;
for (ll i = 1; i <= m; i ++){
dp[i][0] = 1;
for (ll j = 1; j <= n; j ++){
dp[i][j] = dp[i - 1][j];
for (ll k = 1; k <= j and 2 * k <= cnt[i]; k ++){
dp[i][j] += (dp[i - 1][j - k] * comb[cnt[i]][2 * k] % mod) * (comb[j][k] * f[2 * k] % mod);
dp[i][j] %= mod;
}
}
}
ll ans = f[2 * n];
ll last = 0;
for (ll i = 1; i <= n; i ++){
// choose pairs, choose places, choose place for each pair, choose for the rest.
ll val = comb[n][i] * dp[m][i] % mod;
// val = val * f[i] % mod;
// val = val * pwr(2, i) % mod;
val = val * f[2 * n - 2 * i] % mod;
ll sgn = (i % 2 ? -1 : 1);
ans += sgn * val;
ans %= mod;
}
cout << (ans + mod) % mod << endl;
}
/*
I have 2k people
nC2
*
(n - 2)C2
and so on
1 2 3 4 -2
1 2 4 3 -0
1 3 2 4 -0
1 3 4 2 -0
1 4 2 3 -0
1 4 3 2 -2
2 1 3 4 -0
2 1 4 3 -2
2 3 1 4 -0
2 3 4 1 -2
2 4 1 3 -0
2 4 3 1 -0
3 2 1 4 -2
3 2 4 1 -0
3 1 2 4 -0
3 1 4 2 -0
3 4 2 1 -0
3 4 1 2 -2
4 2 3 1 -0
4 2 1 3 -0
4 3 2 1 -2
4 3 1 2 -0
4 1 2 3 -2
4 1 3 2 -0
6 4
138101760
_ _ _ _ _ _ _ _ _ _ _ _
1 : 6C1 * () * f[1]
*/
