#include <cstdio>

 #include <string>

 #include <cstring>

 using namespace std;

 #define MOD 20090717

 int trie[][];

 int o[];

 int fail[];

 int que[];

 int dp[][][];

 int flag[];

 int t;

 void CL()

 {

     memset(trie,-,sizeof(trie));

     memset(dp,,sizeof(dp));

     memset(o,,sizeof(o));

     t = ;

 }

 void insert(char *s,int num)

 {

     int root,i,len;

     len = strlen(s);

     root = ;

     for(i = ;i < len;i ++)

     {

         if(trie[root][s[i]-'a'] == -)

         trie[root][s[i]-'a'] = t ++;

         root = trie[root][s[i]-'a'];

     }

     o[root] |= <<num;

 }

 void build_ac()

 {

     int head,tail,front,i;

     head = tail = ;

     for(i = ;i < ;i ++)

     {

         if(trie[][i] != -)

         {

             fail[trie[][i]] = ;

             que[tail++] = trie[][i];

         }

         else

         {

             trie[][i] = ;

         }

     }

     while(head != tail)

     {

         front = que[head++];

         o[front] |= o[fail[front]];

         for(i = ;i < ;i ++)

         {

             if(trie[front][i] != -)

             {

                 que[tail++] = trie[front][i];

                 fail[trie[front][i]] = trie[fail[front]][i];

             }

             else

             {

                 trie[front][i] = trie[fail[front]][i];

             }

         }

     }

 }

 int main()

 {

     int n,m,r,k,i,j,u,x,y;

     char str[];

     for(i = ;i < ;i ++)

     {

         for(j = ;j < ;j ++)

         {

             if(i&(<<j)) flag[i] ++;

         }

     }

     while(scanf("%d%d%d",&n,&m,&r)!=EOF)

     {

         if(n == &&m == &&r == ) break;

         CL();

         for(i = ;i < m;i ++)

         {

             scanf("%s",str);

             insert(str,i);

         }

         build_ac();

         dp[][][] = ;

         x = ;y = ;

         for(i = ;i < n;i ++)

         {

             memset(dp[y],,sizeof(dp[y]));

             for(j = ;j < t;j ++)

             {

                 for(k = ;k < (<<m);k ++)

                 {

                     if(dp[x][j][k] == ) continue;

                     for(u = ;u < ;u ++)

                     {

                         int temp =  trie[j][u];

                         dp[y][temp][k|o[temp]] += dp[x][j][k];

                         if(dp[y][temp][k|o[temp]] >= MOD)

                         dp[y][temp][k|o[temp]] -= MOD;

                     }

                 }

             }

             swap(x,y);

         }

         int ans = ;

         for(i = ;i < t;i ++)

         {

             for(j = ;j < (<<m);j ++)

             {

                 if(flag[j] >= r)

                 ans = (ans + dp[x][i][j])%MOD;

             }

         }

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

     }

     return ;

 }