#include<stdio.h>
#include<iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<string.h>

#ifdef LOCAL
#define eprintf(...) fprintf(stderr, __VA_ARGS__)
#else
#define NDEBUG
#define eprintf(...) do {} while (0)
#endif
#include<cassert>

using namespace std;

typedef long long LL;
typedef vector<int> VI;

#define REP(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)
#define EACH(i,c) for(__typeof((c).begin()) i=(c).begin(),i##_end=(c).end();i!=i##_end;++i)

template<class T> inline void amin(T &x, const T &y) { if (y<x) x=y; }
template<class T> inline void amax(T &x, const T &y) { if (x<y) x=y; }
template<class Iter> void rprintf(const char *fmt, Iter begin, Iter end) {
    for (bool sp=0; begin!=end; ++begin) { if (sp) putchar(' '); else sp = true; printf(fmt, *begin); }
    putchar('\n');
}

template<unsigned MOD> struct ModInt {
    static const unsigned static_MOD = MOD;
    unsigned x;
    void undef() { x = (unsigned)-1; }
    bool isnan() const { return x == (unsigned)-1; }
    inline int geti() const { return (int)x; }
    ModInt() { x = 0; }
    ModInt(const ModInt &y) { x = y.x; }
    ModInt(int y) { if (y<0 || (int)MOD<=y) y %= (int)MOD; if (y<0) y += MOD; x=y; }
    ModInt(unsigned y) { if (MOD<=y) x = y % MOD; else x = y; }
    ModInt(long long y) { if (y<0 || MOD<=y) y %= MOD; if (y<0) y += MOD; x=y; }
    ModInt(unsigned long long y) { if (MOD<=y) x = y % MOD; else x = y; }
    ModInt &operator+=(const ModInt y) { if ((x += y.x) >= MOD) x -= MOD; return *this; }
    ModInt &operator-=(const ModInt y) { if ((x -= y.x) & (1u<<31)) x += MOD; return *this; }
    ModInt &operator*=(const ModInt y) { x = (unsigned long long)x * y.x % MOD; return *this; }
    ModInt &operator/=(const ModInt y) { x = (unsigned long long)x * y.inv().x % MOD; return *this; }
    ModInt operator-() const { return (x ? MOD-x: 0); }

    ModInt inv() const {
	unsigned a = MOD, b = x; int u = 0, v = 1;
	while (b) {
	    int t = a / b;
	    a -= t * b; swap(a, b);
	    u -= t * v; swap(u, v);
	}
	if (u < 0) u += MOD;
	return ModInt(u);
    }
    ModInt pow(long long y) const {
	ModInt b = *this, r = 1;
	if (y < 0) { b = b.inv(); y = -y; }
	for (; y; y>>=1) {
	    if (y&1) r *= b;
	    b *= b;
	}
	return r;
    }
    friend ModInt operator+(ModInt x, const ModInt y) { return x += y; }
    friend ModInt operator-(ModInt x, const ModInt y) { return x -= y; }
    friend ModInt operator*(ModInt x, const ModInt y) { return x *= y; }
    friend ModInt operator/(ModInt x, const ModInt y) { return x *= y.inv(); }
    friend bool operator<(const ModInt x, const ModInt y) { return x.x < y.x; }
    friend bool operator==(const ModInt x, const ModInt y) { return x.x == y.x; }
    friend bool operator!=(const ModInt x, const ModInt y) { return x.x != y.x; }
};

const LL MOD = 1000000007;
//const LL MOD = 998244353;
typedef ModInt<MOD> Mint;
int N, K, M;
int A[25011];
int prv[411];

Mint dpL[25011][411];
Mint dpR[25011][411];
Mint sums[411];

Mint anti() {
    memset(prv, 0xc0, sizeof prv);
    int len = 0;
    REP (i, M) {
	len = min(len+1, i - prv[A[i]]);
	if (len == K) return 0;
	prv[A[i]] = i;
    }

    if (len == M) {
	dpL[0][0] = 1;
	REP (i, N) {
	    REP (a, K) {
		dpL[i+1][a+1] += dpL[i][a] * (K-a);
		dpR[i+1][a+1] += dpR[i][a] * (K-a);
		if (a+1 >= M) dpR[i+1][a+1] += dpL[i][a] * (K-a);
	    }
	    REP (a, K) {
		sums[a+1] = sums[a] + dpL[i][a];
	    }
	    for (int b=1; b<K; b++) {
		dpL[i+1][b] += sums[K] - sums[b];
		if (b >= M) dpR[i+1][b] += sums[K] - sums[b];
	    }
	    REP (a, K) {
		sums[a+1] = sums[a] + dpR[i][a];
	    }
	    for (int b=1; b<K; b++) {
		dpR[i+1][b] += sums[K] - sums[b];
	    }
	    dpL[i+1][K] = 0;
	    dpR[i+1][K] = 0;
	}

	Mint ret = 0;
	Mint de = 1;
	REP (a, K) ret += dpR[N][a];
	REP (i, M) {
	    de *= K - i;
	}
	return ret / de;
    } else {
	dpR[0][len] = 1;
	REP (i, N) {
	    REP (a, K) {
		dpR[i+1][a+1] += dpR[i][a] * (K - a);
		sums[a+1] = sums[a] + dpR[i][a];
	    }
	    for (int b=1; b<K; b++) dpR[i+1][b] += sums[K] - sums[b];
	    dpR[i+1][K] = 0;
	}

	memset(prv, 0x3f, sizeof prv);
	len = 0;
	for (int i=M; i--;) {
	    len = min(len+1, prv[A[i]] - i);
	    if (len == K) return 0;
	    prv[A[i]] = i;
	}

	dpL[0][len] = 1;
	REP (i, N) {
	    REP (a, K) {
		dpL[i+1][a+1] += dpL[i][a] * (K - a);
		sums[a+1] = sums[a] + dpL[i][a];
	    }
	    for (int b=1; b<K; b++) dpL[i+1][b] += sums[K] - sums[b];
	    dpL[i+1][K] = 0;
	}

	Mint ret = 0;
	REP (i, N-M+1) {
	    Mint a = 0, b = 0;
	    REP (k, K) {
		a += dpL[i][k];
		b += dpR[N-M-i][k];
	    }

	    ret += a * b;
	}
	return ret;
    }
}

void MAIN() {
    scanf("%d%d%d", &N, &K, &M);
    REP (i, M) scanf("%d", A+i), A[i]--;

    Mint ans = (N-M+1) * Mint(K).pow(N-M);
    //eprintf("%d\n", ans.geti());
    ans -= anti();
    printf("%d\n", ans.geti());
}

int main() {
    int TC = 1;
//    scanf("%d", &TC);
    REP (tc, TC) MAIN();
    return 0;
}



Measured memory_bytes: 80640