#include <iostream>
#include <vector>
#include <algorithm>
#include <cstring>
using namespace std;
const int MOD = 1000000007;
const int MAXN = 4007;
int N, M;
int add(int a, int b) { return a -= ((a += b) >= MOD ? MOD : 0); }
int sub(int a, int b) { return a += ((a -= b) < 0 ? MOD : 0); }
int mul(int a, int b) { return (int) ((int64_t) a * b % MOD); }
int inv(int a, int m = MOD) { return (a == 1) ? 1 : m - (int) ((int64_t) m * inv(m % a, a) / a); }
int fact[MAXN], ifact[MAXN];
int single[MAXN], dp[MAXN], tmp[MAXN];
int choose(int n, int k) {
return (n >= k && k >= 0) * mul(fact[n], mul(ifact[k], ifact[n - k]));
}
int main() {
cin >> N >> M; N *= 2;
fact[0] = 1; for (int i = 1; i <= N; ++i) fact[i] = mul(fact[i - 1], i);
ifact[N] = inv(fact[N]); for (int i = N; i >= 1; --i) ifact[i - 1] = mul(ifact[i], i);
int z = 1;
dp[0] = 1;
int t = N / M + 1;
for (int j = 0; j <= t / 2; ++j) single[j] = mul(fact[t], mul(ifact[j], ifact[t - 2 * j]));
for (int s = 0; s < N % M; ++s) {
memset(tmp, 0, sizeof(int) * (z + t / 2));
for (int i = 0; i < z; ++i) {
for (int j = 0; j <= t / 2; ++j) {
tmp[i + j] = add(tmp[i + j], mul(dp[i], single[j]));
}
}
memcpy(dp, tmp, sizeof(int) * (z + t / 2));
z += t / 2;
}
--t;
for (int j = 0; j <= t / 2; ++j) single[j] = mul(fact[t], mul(ifact[j], ifact[t - 2 * j]));
for (int s = N % M; s < M; ++s) {
memset(tmp, 0, sizeof(int) * (z + t / 2));
for (int i = 0; i < z; ++i) {
for (int j = 0; j <= t / 2; ++j) {
tmp[i + j] = add(tmp[i + j], mul(dp[i], single[j]));
}
}
memcpy(dp, tmp, sizeof(int) * (z + t / 2));
z += t / 2;
}
int ans = 0;
for (int i = 0; i < z; ++i) {
int x = dp[i];
x = mul(x, fact[N / 2]);
x = mul(x, ifact[N / 2 - i]);
x = mul(x, fact[N - i * 2]);
if (i & 1) ans = sub(ans, x);
else ans = add(ans, x);
}
cout << ans << endl;
}
