/*
ЗАПУСКАЕМ 
░ГУСЯ░▄▀▀▀▄░РАБОТЯГУ░░
▄███▀░◐░░░▌░░░░░░░
░░░░▌░░░░░▐░░░░░░░
░░░░▐░░░░░▐░░░░░░░
░░░░▌░░░░░▐▄▄░░░░░
░░░░▌░░░░▄▀▒▒▀▀▀▀▄
░░░▐░░░░▐▒▒▒▒▒▒▒▒▀▀▄
░░░▐░░░░▐▄▒▒▒▒▒▒▒▒▒▒▀▄
░░░░▀▄░░░░▀▄▒▒▒▒▒▒▒▒▒▒▀▄
░░░░░░▀▄▄▄▄▄█▄▄▄▄▄▄▄▄▄▄▄▀▄
░░░░░░░░░░░▌▌░▌▌░░░░░
░░░░░░░░░░░▌▌░▌▌░░░░░
░░░░░░░░░▄▄▌▌▄▌▌░░░░░ 
 */
#include <iostream>
#include <complex>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <numeric>
#include <cstring>
#include <ctime>
#include <cstdlib>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <list>
#include <cmath>
#include <bitset>
#include <cassert>
#include <queue>
#include <stack>
#include <iomanip>
#include <deque>
    
     
using namespace std;
template<typename T1, typename T2>inline void chkmin(T1 &x, T2 y) { if (x > y) x = y; }
template<typename T1, typename T2>inline void chkmax(T1 &x, T2 y) { if (x < y) x = y; } 
template<typename T, typename U> inline ostream &operator<< (ostream &_out, const pair<T, U> &_p) { _out << _p.first << ' ' << _p.second; return _out; }
template<typename T, typename U> inline istream &operator>> (istream &_in, pair<T, U> &_p) { _in >> _p.first >> _p.second; return _in; }
template<typename T> inline ostream &operator<< (ostream &_out, const vector<T> &_v) { if (_v.empty()) { return _out; } _out << _v.front(); for (auto _it = ++_v.begin(); _it != _v.end(); ++_it) { _out << ' ' << *_it; } return _out; }
template<typename T> inline istream &operator>> (istream &_in, vector<T> &_v) { for (auto &_i : _v) { _in >> _i; } return _in; }
template<typename T> inline ostream &operator<< (ostream &_out, const set<T> &_s) { if (_s.empty()) { return _out; } _out << *_s.begin(); for (auto _it = ++_s.begin(); _it != _s.end(); ++_it) { _out << ' ' << *_it; } return _out; }
template<typename T> inline ostream &operator<< (ostream &_out, const multiset<T> &_s) { if (_s.empty()) { return _out; } _out << *_s.begin(); for (auto _it = ++_s.begin(); _it != _s.end(); ++_it) { _out << ' ' << *_it; } return _out; }
template<typename T> inline ostream &operator<< (ostream &_out, const unordered_set<T> &_s) { if (_s.empty()) { return _out; } _out << *_s.begin(); for (auto _it = ++_s.begin(); _it != _s.end(); ++_it) { _out << ' ' << *_it; } return _out; }
template<typename T> inline ostream &operator<< (ostream &_out, const unordered_multiset<T> &_s) { if (_s.empty()) { return _out; } _out << *_s.begin(); for (auto _it = ++_s.begin(); _it != _s.end(); ++_it) { _out << ' ' << *_it; } return _out; }
template<typename T, typename U> inline ostream &operator<< (ostream &_out, const map<T, U> &_m) { if (_m.empty()) { return _out; } _out << '(' << _m.begin()->first << ": " << _m.begin()->second << ')'; for (auto _it = ++_m.begin(); _it != _m.end(); ++_it) { _out << ", (" << _it->first << ": " << _it->second << ')'; } return _out; }
template<typename T, typename U> inline ostream &operator<< (ostream &_out, const unordered_map<T, U> &_m) { if (_m.empty()) { return _out; } _out << '(' << _m.begin()->first << ": " << _m.begin()->second << ')'; for (auto _it = ++_m.begin(); _it != _m.end(); ++_it) { _out << ", (" << _it->first << ": " << _it->second << ')'; } return _out; }
#define sz(c) (int)(c).size()
#define all(c) (c).begin(), (c).end()
#define rall(c) (c).rbegin(), (c).rend()
#define left left228
#define right right228
#define next next228
#define rank rank228
#define prev prev228
#define y1 y1228                                                         
#define read(FILENAME) freopen((FILENAME + ".in").c_str(), "r", stdin)
#define write(FILENAME) freopen((FILENAME + ".out").c_str(), "w", stdout)
#define files(FILENAME) read(FILENAME), write(FILENAME)
#define pb push_back
#define x first
#define y second
const string FILENAME = "input";
const int Mod = 1000000007;
const int MAXN = 25025;


int mul(int a, int b) {
    return (1LL * a * b) % Mod;
}


int sum(int a, int b) {
    return (a + b) % Mod;
}


int powm(int a, long long b) {
    int cur = a;
    int res = 1;
    while (b > 0) {
        if (b & 1) {
            res = mul(res, cur);
        }   
        cur = mul(cur, cur);
        b >>= 1;
    }
    return res;
}


int n, k, m;
int a[MAXN];
long long dp[444][MAXN];
long long dp2[444][MAXN];
map<int, int> pos;
int pr[MAXN];
int nx[MAXN];
 

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    //read(FILENAME);
    cin >> n >> k >> m;
    for (int i = 0; i < m; i++) {
        cin >> a[i]; 
        a[i]--;
    }
    for (int i = 1; i < k; i++) {
        dp[i][0] = 1;
    }
    for (int i = 1; i <= n; i++) {
        int cnt = 0;
        for (int j = 1; j < k; j++) {
            cnt = sum(cnt, dp[j][i - 1]);
            dp[j][i] = mul(k - j, dp[j + 1][i - 1]);
            dp[j][i] = sum(dp[j][i], cnt);
        }
    }
    for (int i = 0; i <= n; i++) {
        int cnt = 0;
        for (int j = 1; j < k; j++) {
            cnt = sum(cnt, dp[j][i]);
            dp2[j][i] = cnt;
        }
    }
    pos.clear();
    for (int i = 0; i < m; i++) {
        if (pos.count(a[i])) {
            pr[i] = pos[a[i]];
        } else {
            pr[i] = -1;
        }
        pos[a[i]] = i;
    }
    pos.clear();
    for (int i = m - 1; i >= 0; i--) {
        if (pos.count(a[i])) {
            nx[i] = pos[a[i]];
        } else {
            nx[i] = m;
        }
        pos[a[i]] = i;
    }
    int cur = -1;
    bool good = false;
    for (int i = 0; i < m; i++) {
        chkmax(cur, pr[i]);
        if (i - cur >= k) {
            good = true;
            break;
        }
    }
    int all = mul(n - m + 1, powm(k, n - m));
    if (good) {
        cout << all << "\n";
        return 0;
    }
    int sl = 0;
    int sr = 0;
    while (sl < m && pr[sl] == -1) {
        sl++;
    }
    while (sr < m && nx[m - 1 - sr] == m) {
        sr++;
    }
    if (sl == m) {
        int ans = 0;
        int res = 1;
        for (int len = m; len < k && len < n; len++) {
            if (len > m) {
                res = mul(res, k - (len - 1));
            }
            for (int sh = 0; sh + len + 1 <= n; sh++) {
                int r = n - sh - len - 1;
                ans = sum(ans, mul(res, mul(dp[len][sh], dp2[len][r]))); 
            }
        }
        res = 1;
        for (int len = m; len < k && len <= n; len++) {
            if (len > m) {
                res = mul(res, k - (len - 1));
            }
            ans = sum(ans, mul(res, dp[len][n - len]));
        }
        all = sum(all, Mod - ans);
        cout << all << '\n';
    } else {
        int ans = 0;
        for (int i = 0; i <= n - m; i++) {
            ans = sum(ans, mul(dp[sl][i], dp[sr][n - m - i]));
        }
        all = sum(all, Mod - ans);
        cout << all << '\n';
    }
    return 0;
}        



Measured memory_bytes: 159872