import java.util.*;

class Main {
        public static void main(String args[]) {
                try (Scanner sc = new Scanner(System.in)) {
                        while (true) {
                                int n = sc.nextInt(), x = sc.nextInt();
                                if (n == 0 && x == 0) {
                                        break;
                                }
                                int ans = 0;
                                for (int i = 1; i <= n && i <= x; i++) {
                                        for (int j = i + 1; j < n && i + j <= x && x - i > 2 * j; j++) {
                                                if (x - i - j <= n) {
                                                        ans++;
                                                }
                                        }
                                }
                                System.out.println(ans);
                        }
                }
        }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz