#include "bits/stdc++.h" using namespace std; using ll = long long; const double pi = acos(-1); #define FOR(i,a,b) for (ll i=(a),__last_##i=(b);i<__last_##i;i++) #define RFOR(i,a,b) for (ll i=(b)-1,__last_##i=(a);i>=__last_##i;i--) #define REP(i,n) FOR(i,0,n) #define RREP(i,n) RFOR(i,0,n) #define __GET_MACRO3(_1, _2, _3, NAME, ...) NAME #define rep(...) __GET_MACRO3(__VA_ARGS__, FOR, REP)(__VA_ARGS__) #define rrep(...) __GET_MACRO3(__VA_ARGS__, RFOR, RREP)(__VA_ARGS__) template ostream& operator<<(ostream& os, const vector& v) { REP(i, v.size()) { if (i)os << " "; os << v[i]; }return os; } template ostream& operator<<(ostream& os, const vector>& v) { REP(i, v.size()) { if (i)os << endl; os << v[i]; }return os; } const ll INF = LLONG_MAX; ll MOD = 1000000007; ll _MOD = 1000000009; double EPS = 1e-10; #define int long long inline void my_io() { std::ios::sync_with_stdio(false); std::cin.tie(0); cout << fixed << setprecision(16); //cout << setprecision(10) << scientific << ans << endl; } signed main() { ll n; cin >> n; vector>> dp(n + 1, vector>(2, vector(2, 0))); dp[1][1][0] = 1; FOR(i, 2, n + 1) { dp[i][0][0] += dp[i - 1][1][0]; dp[i][0][0] %= MOD; dp[i][0][1] += dp[i - 1][1][0] + dp[i - 1][0][0]; dp[i][0][1] %= MOD; dp[i][1][0] += dp[i - 1][0][1]; dp[i][1][0] %= MOD; } ll ans = 0; REP(i, 2) { REP(j, 2) { ans += dp[n][i][j]; ans %= MOD; } } cout << ans << endl; }