#include #include #include #include #include #include #include using namespace std; constexpr int P = 1000000007; constexpr int N = 300, K = N * (N - 1) / 2; int dp[K + 1]; int main() { int n, k; cin >> n >> k; dp[0] = 1; for (int i = 2; i <= n; i++) { int k1 = min(k, i * (i - 1) / 2); int64_t t = 0; for (int j = 0; j < i; j++) { t += dp[k1 - j]; } for (int j = k1; j >= 0; j--) { int s = t % P; t -= dp[j]; if (j - i >= 0) t += dp[j - i]; dp[j] = s; } } int64_t r = 0; for (int j = 0; j <= k; j++) { r += dp[j]; } r %= P; cout << r << endl; return 0; }