//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,avx512f") #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DEBUG #include "./CompetitiveProgrammingCpp/Utils/debug.hpp" #include "./CompetitiveProgrammingCpp/Utils/Timer.hpp" #include "./CompetitiveProgrammingCpp/Utils/sample.hpp" #else #define dump(...) templateconstexpr inline auto d_val(T a, T b) { return a; } #endif /* macro */ #define FOR(i, b, e) for(ll i = (ll)(b); i < (ll)(e); ++i) #define RFOR(i, b, e) for(ll i = (ll)((e)-1); i >= (ll)(b); --i) #define REP(i, n) FOR(i, 0, (n)) #define RREP(i, n) RFOR(i, 0, (n)) #define REPC(x,c) for(const auto& x:(c)) #define REPI2(it,b,e) for(auto it = (b); it != (e); ++it) #define REPI(it,c) REPI2(it, (c).begin(), (c).end()) #define RREPI(it,c) REPI2(it, (c).rbegin(), (c).rend()) #define REPI_ERACE2(it, b, e) for(auto it = (b); it != (e);) #define REPI_ERACE(it, c) REPI_ERACE2(it, (c).begin(), (c).end()) #define ALL(x) (x).begin(),(x).end() /* macro func */ template inline auto sort(T& t) { std::sort(ALL(t)); } template inline auto rsort(T& t) { std::sort((t).rbegin(), (t).rend()); } template inline auto chmax(T& t, const S& s) { if(s > t) { t = s; return true; } return false; } template inline auto chmin(T& t, const S& s) { if(s < t) { t = s; return true; } return false; } inline auto BR() { std::cout << "\n"; } /* type define */ using ll = long long; template using V = std::vector; using VS = V; using VL = V; using VVL = V; template using P = std::pair; using PAIR = P; /* using std */ using std::cout; using std::cin; using std::cerr; constexpr char endl = '\n'; /* Initial processing */ struct Preprocessing { Preprocessing() { std::cin.tie(0); std::ios::sync_with_stdio(0); }; }_Preprocessing; /* define hash */ constexpr unsigned int static_random() { return 1u * __TIME__[0] * __TIME__[1] * __TIME__[3] * __TIME__[4] * __TIME__[6] * __TIME__[7]; } template struct Hash { auto operator()(T x) const { return std::hash()(x) ^ static_random(); } }; template<> struct Hash> { auto operator()(const std::pair& x) const { return Hash()(x.first << 31 | x.second); } }; /* input */ template std::istream& operator >> (std::istream& is, std::vector& vec) { for(T& x : vec) is >> x; return is; } /* constant value */ constexpr ll MOD = 1000000007; // constexpr ll MOD = 998244353; //============================================================================================= class ModCalculator { const long long m_mod; const std::vector m_fac; const std::vector m_finv; auto constructFac(long long s) { std::vector fac(s); fac[0] = fac[1] = 1; for(long long i = 2; i < s; ++i) { fac[i] = fac[i - 1] * i; if(fac[i] > m_mod) { fac[i] %= m_mod; } } return fac; } auto constructInv(long long s) { std::vector finv(s); finv[s - 1] = this->pow(m_fac[s - 1], m_mod - 2); for(long long i = s - 2; i >= 0; --i) { finv[i] = finv[i + 1] * (i + 1); if(finv[i] > m_mod) { finv[i] %= m_mod; } } return finv; } public: ModCalculator(long long mod, long long size = 3 * 1e6) : m_mod(mod), m_fac(constructFac(size)), m_finv(constructInv(size)) { } static long long pow(long long a, long long b, long long mod) { a %= mod; long long ans = 1; while(b > 0) { if(b & 1) { ans *= a; if(ans >= mod) { ans %= mod; } } b >>= 1; a *= a; if(a >= mod) { a %= mod; } } return ans; } long long pow(long long a, long long b) const { return pow(a, b, m_mod); } auto fact(int n) const { if(n < 0) { return 0LL; } return m_fac[n]; } auto factInv(int n) const { if(n < 0) { return 0LL; } return m_finv[n]; } auto comb(int n, int r) const { auto val = fact(n) * factInv(r); if(val >= m_mod) { val %= m_mod; } val *= factInv(n - r); if(val >= m_mod) { val %= m_mod; } return val; } auto perm(int n, int r) const { auto val = fact(n) * factInv(n - r); if(val >= m_mod) { val %= m_mod; } return val; } auto inv(int n) const { return pow(n, m_mod - 2); } }calc(MOD); auto solve(ll n) { if(n <= 2) { return 0LL; } VL dp(n + 1); dp[0] = 1; dp[1] = 1; dp[2] = 1; FOR(i, 3, n + 1) REP(l, i) if(l & 1) { auto r = i - l - 1; dp[i] += dp[l] * dp[r] % MOD * calc.comb(i - 1, l) % MOD; dp[i] %= MOD; } return (dp[n] << 1) % MOD; } signed main() { ll n; cin >> n; cout << solve(n) << endl; }