import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		int n = 0;
		int x = 0;
		while (true) {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		}
		System.out.print(sb);
	}
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		int n = 0;
		int x = 0;
		while (true) {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		}
		System.out.print(sb);
	}
} Main public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		int n = 0;
		int x = 0;
		while (true) {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		}
		System.out.print(sb);
	} main {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		int n = 0;
		int x = 0;
		while (true) {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		}
		System.out.print(sb);
	} BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); br new BufferedReader(new InputStreamReader(System.in)) StringBuilder sb = new StringBuilder(); sb new StringBuilder() int n = 0; n 0 int x = 0; x 0 while (true) {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		} true {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		} String[] str = (br.readLine()).split(" "); str (br.readLine()).split(" ") (br.readLine()).split (br.readLine()) br.readLine br " " n = Integer.parseInt(str[0]) n Integer.parseInt(str[0]) Integer.parseInt Integer str[0] str 0 x = Integer.parseInt(str[1]) x Integer.parseInt(str[1]) Integer.parseInt Integer str[1] str 1 if (n == 0 && x == 0) {
				break;
			} n == 0 && x == 0 n == 0 n 0 x == 0 x 0 {
				break;
			} break; int count = 0; count 0 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 sb.append(count).append("\n") sb.append(count).append sb.append(count) sb.append sb count "\n" System.out.print(sb) System.out.print System.out System System.out sb String[] args args public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		int n = 0;
		int x = 0;
		while (true) {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		}
		System.out.print(sb);
	}
} public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		int n = 0;
		int x = 0;
		while (true) {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		}
		System.out.print(sb);
	}
} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		int n = 0;
		int x = 0;
		while (true) {
			String[] str = (br.readLine()).split(" ");
			n = Integer.parseInt(str[0]);
			x = Integer.parseInt(str[1]);
			if (n == 0 && x == 0) {
				break;
			}
			int count = 0;
			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++;
						}
					}
				}
			}
			sb.append(count).append("\n");
		}
		System.out.print(sb);
	}
}