// Hydro submission #670e5bc4f512b2475e9f0f31@1728994245173
/*
Reference: 
- https://qoj.ac/submission/438295
- https://oeis.org/A098273
*/
#include<bits/stdc++.h>
using namespace std;
#define ve vector
#define x first
#define y second
#define ep emplace
#define pb emplace_back
#define de(b) #b,'=',b
#define Sz(k) int((k).size())
#define all(b) begin(b),end(b)
#define rll(k) rbegin(k),rend(k)
namespace BK0717 {
#ifdef Bella
ifstream cin("BK.in"); ofstream cout("BK.out");
void clg(auto x){cerr<<x;} void clg(auto x,auto...y){clg(x),clg(y...);}
#endif
int cn(auto&x,auto y){return x>y?x=y,1:0;}
int cx(auto&x,auto y){return x<y?x=y,1:0;}
template<class T> constexpr T inf=numeric_limits<T>::max()/2;
using LL=long long; using db=double; using pii=pair<int,int>;
constexpr int N=3e4+7,P=998244353;
int inv[N];
struct Mi {
  int n; Mi(){n=0;}
  template<class T>Mi(T m){m>=P&&(m%=P),m<0&&(m+=P),n=m;}
  constexpr int&operator()(){return n;}
  Mi operator+=(Mi m){return (n+=m())<P||(n-=P),*this;}
  Mi operator-=(Mi m){return (n-=m())<0&&(n+=P),*this;}
  Mi operator*=(Mi m){return n=1LL*n*m()%P,*this;}
  Mi operator/=(Mi m){return n=1LL*n*inv[m()]%P,*this;}
  friend Mi operator+(Mi n,Mi m){return n+=m;}
  friend Mi operator-(Mi n,Mi m){return n-=m;}
  friend Mi operator*(Mi n,Mi m){return n*=m;}
  friend Mi operator/(Mi n,Mi m){return n/=m;}
  friend ostream&operator<<(ostream&os,Mi x){return os<<x();}
}fac[N],ifa[N],pw4[N];
int init_com=[] {
  pw4[0]=1;
  for(int i=1;i<N;++i) pw4[i]=pw4[i-1]*4;
  inv[1]=1;
  for(int i=2;i<N;++i) inv[i]=1LL*(P-P/i)*inv[P%i]%P;
  fac[0]=1;
  for(int i=1;i<N;++i) fac[i]=fac[i-1]*i;
  ifa[0]=1;
  for(int i=1;i<N;++i) ifa[i]=ifa[i-1]*inv[i];
  return (fac[N-1]*ifa[N-1])()==1;
} ();
Mi C(int n,int k){return n<k||k<0?0:fac[n]*ifa[n-k]*ifa[k];}
Mi C(int a,int b,int c){return fac[a+b+c]*ifa[a]*ifa[b]*ifa[c];}
Mi f(int a,int b) {
  tie(a,b)=make_pair(b,a-b);
  return pw4[a]*(2*b+1)/(a+b+1)/(2*(a+b)+1)*C(2*b,b)*C(3*a+2*b,a);
}
void Solve() {
  int a,b,c; cin>>a>>b>>c;
  Mi ans=C(a,b,c);
  for(int i=0;i<=min(a,b-1);++i) for(int j=0;j<=min(i,c);++j) ans-=f(i,j)*C(a-i,b-i-1,c-j);
  for(int i=0;i<=min(a,c-1);++i) for(int j=0;j<=min(i,b);++j) ans-=f(i,j)*C(a-i,b-j,c-i-1);
  cout<<ans;
  return;
}
void Main() {
  ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
  int T=1;
  // cin>>T;
  for(;T--;) Solve();
} } main(){BK0717::Main();}