def mul(p,q,mod):
	n=len(p)
	ans=[[0 for i in range(n)] for j in range(n)]
	for i in range(n):
		for j in range(n):
			for k in range(n):
				ans[i][k]+=(p[i][j]*q[j][k])%mod
				if ans[i][k]>=mod:
					ans[i][k]-=mod
	return ans
def my_pow(p,x,mod):
	n=len(p)
	ans=[[0 for i in range(n)]for j in range(n)]
	for i in range(n):
		ans[i][i]=1
	while x>0:
		if x%2==1:
			ans=mul(ans,p,mod)
		x//=2
		p=mul(p,p,mod)
	return ans
MOD=10**9+7
L,N,M=map(int,input().split())
K=list(map(int,input().split()))
s=set()
tmp=0
D=sum(K)+M+1
base=[[0 for i in range(D)]for j in range(D)]
for i in range(M):
	for j in range(D):
		if j<tmp or tmp+K[i]+1<=j:
			base[j][tmp]=1
	for j in range(K[i]):
		base[j+tmp][j+1+tmp]=1
	tmp+=K[i]+1
	base[tmp-1][tmp-1]=1
	s.add(tmp-2)
for i in range(D):
	base[i][D-1]=N-M
tmp=0
for i in range(M):
	tmp+=K[i]-1
	for j in range(D):
		if j!=tmp+1:
			base[tmp][j]=0
	tmp+=2
base=my_pow(base,L,MOD)
ans=pow(N,L,MOD)
for i in range(D):
	if i not in s:
		ans-=base[D-1][i]
print((ans%MOD+MOD)%MOD)