mod=998244353 M=(10**5)*3+1 fac=[1]*M ninv=[1]*M finv=[1]*M for i in range(2,M): fac[i]=fac[i-1]*i%mod ninv[i]=(-(mod//i)*ninv[mod%i])%mod finv[i]=finv[i-1]*ninv[i]%mod def binom(n,k): if n<0 or k<0: if n==k==-1: return 1 return 0 if k>n: return 0 return (fac[n]*finv[k]%mod)*finv[n-k]%mod N,B,W=map(int,input().split()) ans=0 for t,p,q in [[1,2,0],[2,3,1],[1,4,2]]: for c1 in range(B): x=B-1-c1 y=N+1-W-c1-p c2=3*x-y c3=y-2*x if c2<0 or c3<0: continue ans+=t*binom(B-1,c1)*binom(B-1-c1,c2)%mod*binom(W+c3+q-1,c3+q-1) ans%=mod print(ans)