#include int ri() { int n; scanf("%d", &n); return n; } #define MOD 1000000007 template struct ModInt{ int x; ModInt():x(0){} ModInt(long long y):x(y>=0?y%mod:(mod-(-y)%mod)%mod){} ModInt &operator+=(const ModInt &p){ if((x+=p.x)>=mod)x-=mod; return *this; } ModInt &operator-=(const ModInt &p){ if((x+=mod-p.x)>=mod)x-=mod; return *this; } ModInt &operator*=(const ModInt &p){ x=(int)(1LL*x*p.x%mod); return *this; } ModInt &operator/=(const ModInt &p){ *this*=p.inverse(); return *this; } ModInt &operator^=(long long p){ ModInt res = 1; for (; p; p >>= 1) { if (p & 1) res *= *this; *this *= *this; } return *this = res; } ModInt operator-()const{return ModInt(-x);} ModInt operator+(const ModInt &p)const{return ModInt(*this)+=p;} ModInt operator-(const ModInt &p)const{return ModInt(*this)-=p;} ModInt operator*(const ModInt &p)const{return ModInt(*this)*=p;} ModInt operator/(const ModInt &p)const{return ModInt(*this)/=p;} ModInt operator^(long long p)const{return ModInt(*this)^=p;} bool operator==(const ModInt &p)const{return x==p.x;} bool operator!=(const ModInt &p)const{return x!=p.x;} explicit operator int() const { return x; } // added by QCFium ModInt operator=(const int p) {x = p; return ModInt(*this);} // added by QCFium ModInt inverse()const{ int a=x,b=mod,u=1,v=0,t; while(b>0){ t=a/b; a-=t*b; std::swap(a,b); u-=t*v; std::swap(u,v); } return ModInt(u); } friend std::ostream &operator<<(std::ostream &os,const ModInt &p){ return os<>(std::istream &is,ModInt &a){ long long x; is>>x; a=ModInt(x); return (is); } }; typedef ModInt mint; struct MComb { std::vector fact; std::vector inv; MComb (int n) { // O(n + log(mod)) fact = std::vector(n + 1, 1); for (int i = 1; i <= n; i++) fact[i] = fact[i - 1] * mint(i); inv.resize(n + 1); inv[n] = fact[n] ^ (MOD - 2); for (int i = n; i--; ) inv[i] = inv[i + 1] * mint(i + 1); } mint ncr(int n, int r) { return fact[n] * inv[r] * inv[n - r]; } mint npr(int n, int r) { return fact[n] * inv[n - r]; } mint nhr(int n, int r) { assert(n + r - 1 < (int) fact.size()); return ncr(n + r - 1, r); } }; int main() { int n = ri(), m = ri(); MComb com(n + m); int k = ri(); int clearance = n + m - k; mint res = 0; for (int i = 1; i * 2 <= clearance; i++) { if (i > n || i > m) break; mint curn = com.npr(n, i) * com.fact[n - 1] / com.fact[i - 1]; mint curm = com.npr(m, i) * com.fact[m - 1] / com.fact[i - 1]; res += curn * curm / i; } std::cout << res << std::endl; return 0; }