#include <cstdio>

 #include <cstring>

 #define mx 10005

 int opt[mx];

 void rdy(){

     bool prim[mx];

     memset(prim, , sizeof(prim));

     prim[] = ;

     int i, j;

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

         if (prim[i]) continue;

         for (j = i << ; j < mx; j += i) prim[j] = ;

     }

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

         if (prim[i]) continue;

         for (++opt[j = i + ]; j < mx; j += ){

             if (!prim[j] && j + i < mx) ++opt[j + i];

         }

     }

 }

 int main(){

     rdy();

     int a;

     while (scanf("%d", &a), a) printf("%d\n", opt[a]);

     return ;

 }