#include using namespace std; using ll = long long; using pll = pair; #define drep(i, cc, n) for (ll i = (cc); i <= (n); ++i) #define rep(i, n) drep(i, 0, n - 1) #define all(a) (a).begin(), (a).end() #define pb push_back #define fi first #define se second mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count()); const ll MOD1000000007 = 1000000007; const ll MOD998244353 = 998244353; const ll MOD[3] = {999727999, 1070777777, 1000000007}; const ll LINF = 1LL << 60; const int IINF = 1 << 30 - 1; template struct Edge{ int to; T w; Edge(int to_, T w_=1){ to = to_; w=w_; } }; template using Tree = vector>>; template using Graph = vector>>; /* 容量&重み付きエッジ for Dinic */ template struct REdge{ int to; T cap; T cost; int rev; REdge(int to_, T cap_, T cost_=1){ to = to_; cap = cap_; cost = cost_; } REdge(int to_, T cap_, T cost_, int rev_){ to = to_; cap = cap_; cost = cost_; rev = rev_; } }; /* 残余グラフ for Dinic */ template using RGraph = vector>>; template class modint{ long long x; public: modint(long long x=0) : x((x%mod+mod)%mod) {} modint operator-() const { return modint(-x); } bool operator==(const modint& a){ if(x == a) return true; else return false; } bool operator==(long long a){ if(x == a) return true; else return false; } bool operator!=(const modint& a){ if(x != a) return true; else return false; } bool operator!=(long long a){ if(x != a) return true; else return false; } modint& operator+=(const modint& a) { if ((x += a.x) >= mod) x -= mod; return *this; } modint& operator-=(const modint& a) { if ((x += mod-a.x) >= mod) x -= mod; return *this; } modint& operator*=(const modint& a) { (x *= a.x) %= mod; return *this; } modint operator+(const modint& a) const { modint res(*this); return res+=a; } modint operator-(const modint& a) const { modint res(*this); return res-=a; } modint operator*(const modint& a) const { modint res(*this); return res*=a; } modint pow(long long t) const { if (!t) return 1; modint a = pow(t>>1); a *= a; if (t&1) a *= *this; return a; } // for prime mod modint inv() const { return pow(mod-2); } modint& operator/=(const modint& a) { return (*this) *= a.inv(); } modint operator/(const modint& a) const { modint res(*this); return res/=a; } friend std::istream& operator>>(std::istream& is, modint& m) noexcept { is >> m.x; m.x %= mod; if (m.x < 0) m.x += mod; return is; } friend ostream& operator<<(ostream& os, const modint& m){ os << m.x; return os; } }; using mint = modint; const ll MAX = 510000; mint fac[MAX], finv[MAX], inv[MAX]; void cominit(){ fac[0] = fac[1] = 1; finv[0] = finv[1] = 1; inv[1] = 1; for(ll i=2; i> n >> k; mint ans = 0; if(k%2==0){ ans += com(2*n+4, k); //180度回転 ans += com(n+2, k/2); //反転 if(n%2==1){ //(上中央, 下中央)=(塗らない, 塗らない) if(k <= 2*n+2) ans += com(n+1, k/2); //(上中央, 下中央)=(塗る, 塗る) if(k-2 <= 2*n+2) ans += com(n+1, (k-2)/2); }else{ ans += com(n+2, k/2); } //反転+180度回転 ans += com(n+2, k/2); }else{ ans = com(2*n+4, k); //反転 if(n%2==1){ //(上中央, 下中央)=(塗る, 塗らない) if(k-1 <= 2*n+2) ans += com(n+1, (k-1)/2); //(上中央, 下中央)=(塗らない, 塗る) if(k-1 <= 2*n+2) ans += com(n+1, (k-1)/2); } } ans /= 4; cout << ans << endl; }