#include "bits/stdc++.h" #define REP(i,num) for(ll i=0;i<(num);++i) #define FOR(i,c,num) for(ll (i)=(c);(i)<(num);++(i)) #define LOOP(i) while(i--) #define ALL(c) c.begin(),c.end() #define PRINTALL(c) for(auto pitr=c.begin();pitr!=c.end();++pitr){cout<<*pitr;if(next(pitr,1)!=c.end())cout<<' ';}cout<& lhs,const pair& rhs){return lhs.c comp rhs.c;} using namespace std; using ll = long long; using vll = vector; using vvll = vector>; constexpr ll atcoder_mod = 1e9+7; template T in(){ T x; cin >> x; return (x); } template> C vecin(int N){ C x(N);REP(i,N){ x[i]=in(); }return x; } void vout(){ cout << endl; } template void vout(Head&& h,Tail&&... t){ cout << ' ' << h;vout(forward(t)...); } void out(){ cout << endl; } template void out(Head&& h,Tail&&... t){ cout << h;vout(forward(t)...); } template bool chmax(T& a,T b){ if(a bool chmin(T& a,T b){ if(a>b){ a=b;return true; }return false; } int main(){ cin.tie(0); ios::sync_with_stdio(false); cout<1) A[1] = 1; for(int i=2;i=0;i--){ C[i] = (C[i+1]+A[i])%atcoder_mod; } ll S=0; REP(i,N){ S += (A[i]*C[i])%atcoder_mod; S %= atcoder_mod; } out(S); return 0; }