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#include "bits/stdc++.h"

using namespace std;
#define PB push_back
#define LL long long
#define int LL
#define FOR(i,a,b) for (int i = (a); i <= (b); i++)
#define FORD(i,a,b) for (int i = (a); i >= (b); i--)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define st first
#define nd second
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())
#define VI vector<int>
#define PII pair<int,int>
#define LD long double

template<class C> void mini(C& a4, C b4) { a4 = min(a4, b4); }
template<class C> void maxi(C& a4, C b4) { a4 = max(a4, b4); }

template<class TH> void _dbg(const char *sdbg, TH h){cerr<<sdbg<<"="<<h<<"\n";}
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;cerr<<"="<<h<<","; _dbg(sdbg+1, a...);
}

template<class T> ostream &operator<<(ostream &os, vector<T> V){
  os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]";
} 

template<class L, class R> ostream &operator<<(ostream &os, map<L,R> V){
  os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]";
} 
template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
  return os << "(" << P.st << "," << P.nd << ")";
}


#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

const LD kEps = 1e-9;
const LD kPi = 2 * acos(0);
int Sq(int x) { return x * x; }
struct Point {
  int x, y;
  Point() {}
  Point(int a, int b) : x(a), y(b) {}
  Point(const Point& a) : x(a.x), y(a.y) {}
  void operator=(const Point& a) { x = a.x; y = a.y; }
  Point operator+(const Point& a) const { Point p(x + a.x, y + a.y); return p; }
  Point operator-(const Point& a) const { Point p(x - a.x, y - a.y); return p; }
  Point operator*(int a) const { Point p(x * a, y * a); return p; }
  Point operator/(int a) const { assert(a != 0); Point p(x / a, y / a); return p; }
  Point& operator+=(const Point& a) { x += a.x; y += a.y; return *this; }
  Point& operator-=(const Point& a) { x -= a.x; y -= a.y; return *this; }
  Point& operator*=(int a) { x *= a; y *= a; return *this;}
  Point& operator/=(int a) { assert(a != 0); x /= a; y /= a; return *this; }
  
  bool IsZero() const { return x == 0 && y == 0; }
  bool operator==(const Point& a) const { return (*this - a).IsZero(); }
  bool operator!=(const Point& a) const { return !(*this - a).IsZero(); }
  int CrossProd(const Point& a) const { return x * a.y - y * a.x; }
  int CrossProd(Point a, Point b) const { a -= *this; b -= *this; return a.CrossProd(b); }
  int DotProd(const Point& a) const { return x * a.x + y * a.y; }
  LD Angle() const { return atan2(y, x); }
  static bool LexCmp(const Point& a, const Point& b) {
    if (a.x != b.x) { return a.x < b.x; }
    return a.y < b.y;
  }
  int SqNorm() { return x * x + y * y; }
  friend ostream& operator<<(ostream& out, Point m);
};

ostream& operator<<(ostream& out, Point p) {
  out << "(" << p.x << ", " << p.y << ")"; return out;
}

int is_sq(int a){
  int tmp = sqrt(a);
  return tmp * tmp == a;
}

int sq(int a){
  return a * a;
}

int dist(int x, int y){
  return x * x + y * y;
}

vector<Point> get_sides(int maxLen){
  vector<Point> res;
  FOR(i, 1, maxLen){
    REP(j, i){
      if(__gcd(i, j) != 1)
        continue;
      if(!is_sq(dist(i, j)))
        continue;
      if(dist(i, j) > maxLen * maxLen)
        break;
      debug(i, j);
      for(int a : {-i, i}){
        for(int b : {-j, j}){
          res.push_back(Point(a,b));
          res.push_back(Point(b,a));
        }
      }
    }
  }
  sort(ALL(res), Point::LexCmp);
  res.resize(unique(ALL(res)) - res.begin());
  return res;
}

map<PII, uint32_t> mapka;
Point NONE(-1,-1);
vector<Point> sides;
vector<Point> acc;
int maxSides = 0;
void bt(Point cur, Point prev = NONE, int maxx = 0, int minx = 0, int maxy = 0){
  maxi(maxx, cur.x);
  mini(minx, cur.x);
  maxi(maxy, cur.y);
  if(cur.IsZero() && prev != NONE){
    maxi(maxSides, SZ(acc));
    mapka[{maxx - minx, maxy}]++;
    return;
  }
  for(auto s: sides){
    s += cur;
    if(s.y < 0){
      continue;
    }
    if(prev == NONE){
      if(s.y == 0)
        continue;
      goto nxt;
    }
    if(s == Point(0,0) && prev != Point(0,0)){
      goto nxt;
    }
    {
      int cpd1= prev.CrossProd(cur, s);
      int cpd2 = cur.CrossProd(s);
      if(cpd1 <= 0 || cpd2 <= 0){
        continue;
      }
    }
nxt:;
    acc.PB(cur);
    bt(s, cur, maxx, minx, maxy);
    acc.pop_back();
  }
}

int32_t main(int32_t, char ** argv) {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int x, y, k;
  cin>>x>>y>>k;
  sides = get_sides(k);
  debug(sides.size());
  uint32_t res = 0;
  if(k <= 15){
    bt(Point(0,0));
    debug(SZ(mapka));
    for(auto rec: mapka){
      uint32_t tx = max(0LL, x- rec.st.st);
      uint32_t ty = max(0LL, y- rec.st.nd);
      res += tx * ty * rec.nd;
    }
  } else{
    bt(Point(0,0));
    cout<<mapka<<endl;
  }
  cout<<res<<endl;
}