This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define ve vector<int>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define pi pair<int,int>
#define all(v) v.begin(),v.end()
#define si(v) (int)v.size()
#define en '\n'
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define ordered_muiltiset tree<int, null_type,less_equal<>, rb_tree_tag,tree_order_statistics_node_update>
//#define int long long
using namespace std;
//using namespace __gnu_pbds;
typedef long long ll;
typedef unsigned long long ull;
const int N = 2e3 + 228;
const int big = 1e9 + 228;
const ll llbig = 1e18 + 228;
const ll md = 1e9 + 7;
//ordered_set os; // os.order_of_key(4), (*os.find_by_order(5))
//#undef int
int main(){
    //#define int long long
    iostream::sync_with_stdio(false); cin.tie(0); ios_base::sync_with_stdio(false); cout.tie(0);
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    ll n;
    cin >> n;
    ll ans = 0ll;
    for (int i = 1; i <= n; i++){
        ll cur = n * (0ll + n - i + 1) / 2ll;
        cur %= md;
        ans += cur;
        ans %= md;
    }
    cout << ans;
    return 0;
}
/*
*/
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