#include <bits/stdc++.h>
using namespace std;
#define MOD 1000000007
#define ll long long int
#define ull unsigned long long
#define si set <ll>
#define vi vector <ll>
#define popcount(x) __builtin_popcountll(x)
#define mii map <ll,ll>
#define vpi vector <pair <ll,ll> >
#define sz(c) (ll)c.size()
#define fr first
#define fastio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define sc second
#define pb push_back
#define mp make_pair
#define all(a) (a).begin(),(a).end()
#define mem0(a) memset(a,0,sizeof(a))
#define rep(i,a,n) for(ll i=a ; i<n ; i++)
#define ld long double
const ll INF = __LONG_LONG_MAX__;
#define rall(a) (a).rbegin(),(a).rend()
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization ("unroll-loops")

ll power(ll b,ll e,ll m)
{
  if(b==0) return 0;
  if(e==0) return 1;
  if(e&1) return b*power(b*b%m,e/2,m)%m;
  return power(b*b%m,e/2,m);
}
ll power( ll b, ll e)
{
  if(b==0) return 0;
  if(e==0) return 1;
  if(e&1) return b*power(b*b,e/2);
  return power(b*b,e/2);
}  
bool isPowerOfTwo(ll x)
{
    // x will check if x == 0 and !(x & (x - 1)) will check if x is a power of 2 or not
    return (x && !(x & (x - 1)));
}

const int MAX = 1000001; 
  
// array to store prime factors 
int factor[MAX] = { 0 }; 
  
// function to generate all prime factors 
// of numbers from 1 to 10^6 
void generatePrimeFactors() 
{ 
    factor[1] = 1; 
  
    // Initializes all the positions with their value. 
    for (int i = 2; i < MAX; i++) 
        factor[i] = i; 
  
    // Initializes all multiples of 2 with 2 
    for (int i = 4; i < MAX; i += 2) 
        factor[i] = 2; 
  
    // A modified version of Sieve of Eratosthenes to 
    // store the smallest prime factor that divides 
    // every number. 
    for (int i = 3; i * i < MAX; i++) { 
        // check if it has no prime factor. 
        if (factor[i] == i) { 
            // Initializes of j starting from i*i 
            for (int j = i * i; j < MAX; j += i) { 
                // if it has no prime factor before, then 
                // stores the smallest prime divisor 
                if (factor[j] == j) 
                    factor[j] = i; 
            } 
        } 
    } 
} 
  
// function to calculate number of factors 
int calculateNoOFactors(int n) 
{ 
    if (n == 1) 
        return 1; 
  
    int ans = 1; 
  
    // stores the smallest prime number 
    // that divides n 
    int dup = factor[n]; 
  
    // stores the count of number of times 
    // a prime number divides n. 
    int c = 1; 
  
    // reduces to the next number after prime 
    // factorization of n 
    int j = n / factor[n]; 
  
    // false when prime factorization is done 
    while (j != 1) { 
        // if the same prime number is dividing n, 
        // then we increase the count 
        if (factor[j] == dup) 
            c += 1; 
  
        /* if its a new prime factor that is factorizing n,  
           then we again set c=1 and change dup to the new  
           prime factor, and apply the formula explained  
           above. */
        else { 
            dup = factor[j]; 
            ans = ans * (c + 1); 
            c = 1; 
        } 
  
        // prime factorizes a number 
        j = j / factor[j]; 
    } 
  
    // for the last prime factor 
    ans = ans * (c + 1); 
  
    return ans; 
}


ll calc(ll x)
{
  ll ans=0;
  for(int i=1;i*i<=x;i++)
  {
    if(x%i==0)
    {
      if((x/i)!=i)
        ans+=2;
      else ans+=1;
    }
  }
  return ans;
}

void solve()
{
  fastio
  generatePrimeFactors(); 
  ll n;
  cin>>n;
  ll ans=0;
  for(ll i=1;i<n;i++)
  {
    ll x=n-i;
    ans+=calculateNoOFactors(x);
  }
  cout<<ans;
}

int main()
{
  fastio
  ll tt=1;
  // cin>>tt;
  while(tt--)
  {
      solve();
      cout<<"\n";
  }
}

Measured memory_bytes: 7472