#include "stdio.h"
int main()
{
int x,y,n,j,s;
while( scanf("%d%d",&x,&y)!=EOF)
{
if( x==0 && y==0 )
break;
else {
for( n=x; n<=y; n++ )
{
s=n*n+n+41;
for( j=2; j<=s/2; j++ )
{
if( s%j==0 )
{
printf("Sorry\n");
break;
}
}
}
}
printf("OK\n");
}
}