
import java.io.InputStreamReader;
import java.util.Scanner;

class Main {
	public static void main(String[] args) throws Exception {

		Scanner scanner = new Scanner(System.in);


		while (true) {
			int count = 0;
			int n = scanner.nextInt();
			int x = scanner.nextInt();
			if (n == 0 && x == 0) {
				break;
			} for(int i = 1; i <= (n - 2); i++){
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			}
			System.out.println(count);
		}
	}
} import java.io.InputStreamReader; InputStreamReader java.io import java.util.Scanner; Scanner java.util class Main {
	public static void main(String[] args) throws Exception {

		Scanner scanner = new Scanner(System.in);


		while (true) {
			int count = 0;
			int n = scanner.nextInt();
			int x = scanner.nextInt();
			if (n == 0 && x == 0) {
				break;
			} for(int i = 1; i <= (n - 2); i++){
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			}
			System.out.println(count);
		}
	}
} Main public static void main(String[] args) throws Exception {

		Scanner scanner = new Scanner(System.in);


		while (true) {
			int count = 0;
			int n = scanner.nextInt();
			int x = scanner.nextInt();
			if (n == 0 && x == 0) {
				break;
			} for(int i = 1; i <= (n - 2); i++){
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			}
			System.out.println(count);
		}
	} main {

		Scanner scanner = new Scanner(System.in);


		while (true) {
			int count = 0;
			int n = scanner.nextInt();
			int x = scanner.nextInt();
			if (n == 0 && x == 0) {
				break;
			} for(int i = 1; i <= (n - 2); i++){
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			}
			System.out.println(count);
		}
	} Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) while (true) {
			int count = 0;
			int n = scanner.nextInt();
			int x = scanner.nextInt();
			if (n == 0 && x == 0) {
				break;
			} for(int i = 1; i <= (n - 2); i++){
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			}
			System.out.println(count);
		} true {
			int count = 0;
			int n = scanner.nextInt();
			int x = scanner.nextInt();
			if (n == 0 && x == 0) {
				break;
			} for(int i = 1; i <= (n - 2); i++){
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			}
			System.out.println(count);
		} int count = 0; count 0 int n = scanner.nextInt(); n scanner.nextInt() scanner.nextInt scanner int x = scanner.nextInt(); x scanner.nextInt() scanner.nextInt scanner if (n == 0 && x == 0) {
				break;
			} n == 0 && x == 0 n == 0 n 0 x == 0 x 0 {
				break;
			} break; for(int i = 1; i <= (n - 2); i++){
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			} int i = 1; int i = 1; i 1 i <= (n - 2) i (n - 2) n 2 i++ i++ i {
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			} {
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			} for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				} int j = i + 1; int j = i + 1; j i + 1 i 1 j <= (n - 1) j (n - 1) n 1 j++ j++ j {
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				} {
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				} for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					} int k = j + 1; int k = j + 1; k j + 1 j 1 k <= n k n k++ k++ k {
						if((i + j + k) == x){
							count++;
						}
					} {
						if((i + j + k) == x){
							count++;
						}
					} if((i + j + k) == x){
							count++;
						} (i + j + k) == x (i + j + k) i + j + k i j k x {
							count++;
						} count++ count System.out.println(count) System.out.println System.out System System.out count String[] args args

import java.io.InputStreamReader;
import java.util.Scanner;

class Main {
	public static void main(String[] args) throws Exception {

		Scanner scanner = new Scanner(System.in);


		while (true) {
			int count = 0;
			int n = scanner.nextInt();
			int x = scanner.nextInt();
			if (n == 0 && x == 0) {
				break;
			} for(int i = 1; i <= (n - 2); i++){
				for(int j = i + 1; j <= (n - 1); j++){
					for(int k = j + 1; k <= n; k++){
						if((i + j + k) == x){
							count++;
						}
					}
				}
			}
			System.out.println(count);
		}
	}
}