#include <fstream>
using namespace std;
ifstream f("pascal.in");
ofstream g("pascal.out");
int fr[6][5000001],n,i,j,d;
int ndiv(int n,int k){
int nr=0;
while(n%k==0){
    n=n/k;
    nr++;
}
return nr;
}
int main()
{
    f>>n>>d;
    for(i=2;i<=n;i++){
        fr[2][i]=fr[2][i-1]+ndiv(i,2);
        fr[3][i]=fr[3][i-1]+ndiv(i,3);
        fr[5][i]=fr[5][i-1]+ndiv(i,5);
    }
    return 0;
}