#include<bits/stdc++.h>
# define int long long
# define rep(i, j, k) for (int i = j; i <= k; ++i)
using namespace std;

int mod, fac[50005], inv[50005];
int n, p, dp[50005], pre[50005], ace[50005];
int power(int a, int p)
{
	int ans = 1;
	for (; p; p >>= 1) {if (p & 1) (ans *= a) %= mod; (a *= a) %= mod;}
	return ans;
}
void pr()
{
	fac[0] = inv[0] = 1;
	rep(i, 1, 50000) fac[i] = fac[i - 1] * i % mod;
	inv[50000] = power(fac[50000], mod - 2);
	for (int i = 49999; i; --i) inv[i] = inv[i + 1] * (i + 1) % mod;
}
signed main()
{
//	freopen("ex_3.in", "r", stdin);
//	freopen("c.out", "w", stdout);
	ios::sync_with_stdio(false); cin.tie(0), cout.tie(0);
	cin >> n >> mod;
	pr();
	for (int i = n; i; --i)
	{
		memset(dp, 0, sizeof(dp));
		rep(j, i, n) dp[j] = fac[n - i + 1];
		int prm = 0;
		for (int k = n; k >= i; --k) (dp[k] += prm) %= mod, (prm += (fac[2 * n - k - i + 2] * inv[2 * n - 2 * k + 3] - fac[2 * n - k - i + 1] * inv[2 * n - 2 * k + 2] + mod * mod) % mod * pre[k]) %= mod,
			(prm += fac[2 * n - k - i + 2] * inv[2 * n - 2 * k + 3] % mod * ace[k]) %= mod;
		ace[i] = dp[i]; rep(j, i + 1, n) (pre[i] += dp[j]) %= mod;
	}
	int ans = 1;
	rep(i, 1, n) (ans *= 2 * i - 1) %= mod;
	cout << (ans - dp[1] + mod) % mod << '\n';
//	cerr << dp[1] << '\n';
	return 0;
}