#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

char*mmap();
#define rd(v) int v=0;{int _c;while(_c=*rp++-48,_c>=0)v=v*10+_c;}

#define wt_rev(v) {long _z=v;do*--wp=_z%10+48;while(_z/=10);}

char vis[50000001];

main(){
	char*rp=mmap(0l,1l<<25,1,2,0,0ll);
	rd(n);
	long res=0;
	for(long i=1;i<=n;++i){
		if(!vis[i]){
			long count=1;
			for(int j=2,ijj;ijj=i*j*j,ijj<=n;++j){
				vis[ijj]=1;
				count+=1;
			}
			res+=count*count;
		}
	}

	char wbuf[64],*wp=wbuf+sizeof wbuf;
	wt_rev(res);
	write(1,wp,wbuf+sizeof wbuf-wp);
	_exit(0);
}