// Copyright (C) 2017 __debug.

// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; version 3

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program; If not, see <http://www.gnu.org/licenses/>.


#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/priority_queue.hpp>

#define x first
#define y second
#define MP std::make_pair
#define SZ(x) ((int)(x).size())
#define ALL(x) (x).begin(), (x).end()
#define DEBUG(...) fprintf(stderr, __VA_ARGS__)
#ifdef __linux__
#define getchar getchar_unlocked
#define putchar putchar_unlocked
#endif

using std::pair;
using std::vector;
using std::string;

typedef long long LL;
typedef pair<int, int> Pii;

const int oo = 0x3f3f3f3f;

template<typename T> inline bool chkmax(T &a, T b) { return a < b ? a = b, true : false; }
template<typename T> inline bool chkmin(T &a, T b) { return b < a ? a = b, true : false; }
string procStatus()
{
    std::ifstream t("/proc/self/status");
    return string(std::istreambuf_iterator<char>(t), std::istreambuf_iterator<char>());
}
template<typename T> T read(T &x)
{
    int f = 1;
    char ch = getchar();
    for (; !isdigit(ch); ch = getchar())
        f = (ch == '-' ? -1 : 1);
    for (x = 0; isdigit(ch); ch = getchar())
        x = 10 * x + ch - '0';
    return x *= f;
}
template<typename T> void write(T x)
{
    if (x == 0) {
        putchar('0');
        return;
    }
    if (x < 0) {
        putchar('-');
        x = -x;
    }
    static char s[20];
    int top = 0;
    for (; x; x /= 10)
        s[++top] = x % 10 + '0';
    while (top)
        putchar(s[top--]);
}
// EOT

const int MAXN = 105;
const int MOD = 1e9 + 7;

int N;
int A[MAXN];

void input()
{
    read(N);
    for (int i = 1; i <= 2 * N - 1; ++i) {
        read(A[i]);
    }
}

void solve()
{
    std::sort(A + 1, A + 2 * N);

    static int dp[MAXN][MAXN][MAXN];

    dp[N-1][1][1] = 1;
    for (int i = N - 1; i >= 1; --i) {
        for (int j = 1; j <= 2 * N - 1; ++j) {
            for (int k = 1; k <= j; ++k) {
                if (!dp[i][j][k])
                    continue;
                int j0 = j + (A[i] != A[i+1]) + (A[2*N-i] != A[2*N-i-1]);
                int k0 = k + (A[i] != A[i+1]);
                for (int l = 1; l < k0; ++l) {
                    (dp[i-1][j0-(k0-l-1)][l] += dp[i][j][k]) %= MOD;
                }
                (dp[i-1][j0][k0] += dp[i][j][k]) %= MOD;
                for (int l = k0 + 1; l <= j0; ++l) {
                    (dp[i-1][j0-(l-k0-1)][k0+1] += dp[i][j][k]) %= MOD;
                }
            }
        }
    }

    int ans = 0;
    for (int j = 1; j <= 2 * N - 1; ++j) {
        for (int k = 1; k <= j; ++k) {
            (ans += dp[0][j][k]) %= MOD;
        }
    }

    printf("%d\n", ans);
}

int main()
{
#ifdef __DEBUG
    freopen("F.in", "r", stdin);
    freopen("F.out", "w", stdout);
#endif

    input();
    solve();

    return 0;
}

// 绿树村边合，青山郭外斜。
//     -- 孟浩然《过故人庄》


Measured memory_bytes: 3456