#include using namespace std; #include using namespace atcoder; using mint=atcoder::modint998244353; #define int long long template struct factional_prime{ long long inv_[MAX_N+1]; long long fac_[MAX_N+1]; long long fac_inv_[MAX_N+1]; factional_prime(){ inv_[0]=0;inv_[1]=fac_[0]=fac_[1]=fac_inv_[0]=fac_inv_[1]=1; for(long long i=2;i<=MAX_N;i++){ inv_[i]=((mod-mod/i)*inv_[mod%i])%mod; fac_[i]=(fac_[i-1]*i)%mod; fac_inv_[i]=(fac_inv_[i-1]*inv_[i])%mod; } } long long inv(long long n){ if(n<0)return 0; return inv_[n]; } long long fac(long long n){ if(n<0)return 0; return fac_[n]; } long long finv(long long n){ if(n<0)return 0; return fac_inv_[n]; } long long nCr(long long n,long long r){ if(n fp; signed main(){ int n;cin>>n; mint ans=0; for(int i=0;3*i<=n;i++){ ans+=(i%2?-1:1)*mint(fp.nCr(n,i))*fp.nCr(2*n-3*i-1,n-1); } ans=(ans-1)/2; cout<