#define _USE_MATH_DEFINES #include //cin, cout #include //vector #include //sort,min,max,count #include //string,getline, to_string #include //abs(int) #include //swap, pair #include //deque #include //INT_MAX #include //bitset #include //sqrt, ceil. M_PI, pow, sin #include //fixed #include //setprecision #include //stringstream #include //gcd, assumlate #include //randam_device #include //numeric_limits #include //tm using namespace std; constexpr int64_t D_MOD = 1000000007; constexpr int64_t F_MOD = 998244353; int main() { int Q; cin >> Q; vector R = { 1,1 }; vector E = { 1,3 }; int max_idx = 1; int64_t RR = 0, EE = 0; int N; for (int i = 0; i < Q; i++) { cin >> N; if (N > max_idx) { for (int j = max_idx + 1; j < N; j++) { R.push_back(((R.at(j - 1) % F_MOD) + (R.at(j - 2) % F_MOD)) % F_MOD); E.push_back(((E.at(j - 1) % F_MOD) + (E.at(j - 2) % F_MOD)) % F_MOD); } max_idx = N - 1; RR = (R.at(N - 1) * R.at(N - 1))%F_MOD; EE = (E.at(N - 1) * E.at(N - 1))%F_MOD; } cout << ((5 * RR - EE) % F_MOD + F_MOD) % F_MOD << endl; } return 0; }