#include using namespace std; using lint = long long int; using pint = pair; using plint = pair; struct fast_ios { fast_ios(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_; #define FOR(i, begin, end) for(int i=(begin),i##_end_=(end);i=i##_begin_;i--) #define REP(i, n) FOR(i,0,n) #define IREP(i, n) IFOR(i,0,n) template istream &operator>>(istream &is, vector &vec){ for (auto &v : vec) is >> v; return is; } template ostream &operator<<(ostream &os, const vector &vec){ os << "["; for (auto v : vec) os << v << ","; os << "]"; return os; } template ostream &operator<<(ostream &os, const deque &vec){ os << "deq["; for (auto v : vec) os << v << ","; os << "]"; return os; } template ostream &operator<<(ostream &os, const set &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; } template ostream &operator<<(ostream &os, const unordered_set &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; } template ostream &operator<<(ostream &os, const multiset &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; } template ostream &operator<<(ostream &os, const unordered_multiset &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; } template ostream &operator<<(ostream &os, const pair &pa){ os << "(" << pa.first << "," << pa.second << ")"; return os; } template ostream &operator<<(ostream &os, const map &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; } template ostream &operator<<(ostream &os, const unordered_map &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; } template void ndarray(vector &vec, int len) { vec.resize(len); } template void ndarray(vector &vec, int len, Args... args) { vec.resize(len); for (auto &v : vec) ndarray(v, args...); } template bool mmax(T &m, const T q) { if (m < q) {m = q; return true;} else return false; } template bool mmin(T &m, const T q) { if (m > q) {m = q; return true;} else return false; } template pair operator+(const pair &l, const pair &r) { return make_pair(l.first + r.first, l.second + r.second); } template pair operator-(const pair &l, const pair &r) { return make_pair(l.first - r.first, l.second - r.second); } #define dbg(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ") " << __FILE__ << endl; #define FI first #define SE second #define ALL(x) (x).begin(), (x).end() #define SZ(x) ((lint)(x).size()) #define POW2(n) (1LL << (n)) constexpr lint MOD = 1000000007; vector fac, facInv, inv; void facInit(int nmax) { fac = facInv = inv = vector(nmax + 1, 1); for (int i = 2; i <= nmax; i++) { fac[i] = fac[i-1] * i % MOD; inv[i] = MOD - inv[MOD%i] * (MOD/i) % MOD; facInv[i] = facInv[i-1] * inv[i] % MOD; } } lint nCr(int n, int r) { if (n= (int)fac.size()) facInit(n); return (fac[n] * facInv[r] % MOD) * facInv[n-r] % MOD; } lint nPr(int n, int r) { if (n= (int)fac.size()) facInit(n); return fac[n] * facInv[n-r] % MOD; } lint power(lint x, lint n, lint mod=MOD) { lint ans = 1; while (n>0) { if (n & 1) (ans *= x) %= mod; (x *= x) %= mod; n >>= 1; } return ans; } lint doublefac(lint n) { if (n < 0) return 0; lint k = (n + 1) / 2; if (n & 1) return fac[k * 2] * power(facInv[2], k) % MOD * power(fac[k], MOD - 2) % MOD; else return fac[k] * power(facInv[2], k) % MOD; } lint ret; lint N, M; void solve(lint now) { if (now + (M - now) / 2 > M) return; ret += nCr(M, now + (M - now) / 2); solve(now + N * 2); } int main() { cin >> N >> M; if (N == 1) { puts("1"); return 0; } facInit(M); ret = 0; if (M % 2 == 0) { solve(0); solve(2 * N); } else { solve(1); solve(2 * N - 1); } cout << ret << endl; }