include <bits/stdc++.h>

using namespace std; int main(){

for(int i=23;;i+=2){
	for(int day=1,x=i;day<=5&&x>=11;day++){
		if(day==5&&x==11){
			cout<<i<<endl;
			return 0;
		}
		if((x+1)%(day+1)==0){
			x-=(x+1)/(day+1);
		}
		else{
			break;
		}
	}
}
return 0;

}