#include using namespace std; typedef long long ll; typedef vector VI; typedef vector VVI; typedef vector VL; typedef vector> VVL; typedef pair Pair; typedef tuple tpl; #define ALL(a) (a).begin(),(a).end() #define SORT(c) sort((c).begin(),(c).end()) #define REVERSE(c) reverse((c).begin(),(c).end()) #define EXIST(m,v) (m).find((v)) != (m).end() #define LB(a,x) lower_bound((a).begin(), (a).end(), x) - (a).begin() #define UB(a,x) upper_bound((a).begin(), (a).end(), x) - (a).begin() #define FOR(i,a,b) for(int i=(a);i<(b);++i) #define REP(i,n) FOR(i,0,n) #define RFOR(i,a,b) for(int i=(a)-1;i>=(b);--i) #define RREP(i,n) RFOR(i,n,0) #define en "\n" constexpr double EPS = 1e-9; constexpr double PI = 3.1415926535897932; constexpr int INF = 2147483647; constexpr long long LINF = 1LL<<60; constexpr long long MOD = 998244353; // 1000000007; template inline bool chmax(T& a, T b){if(a inline bool chmin(T& a, T b){if(a>b){a=b;return true;}return false;} #include using mint = atcoder::modint998244353; void Main(){ int N; cin >> N; VI A(N); REP(i,N) cin >> A[i]; mint dp[N+1][2], p = mint(3).inv(); dp[1][0] = 1 - p; dp[1][1] = p; FOR(i,2,N+1){ dp[i][0] = dp[i-1][1] * (1-p) + dp[i-1][0] * p; dp[i][1] = dp[i-1][1] * p + dp[i-1][0] * (1-p); } int ans = dp[N][0].val(); cout << ans << en; return; } int main(void){ cin.tie(0);cout.tie(0);ios_base::sync_with_stdio(0);cout<>t; while(t--) Main(); return 0; }