import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		StringBuilder output = new StringBuilder();
		int count = 0;
		
		while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		}
		System.out.print(output);
		scan.close();
	}

} import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		StringBuilder output = new StringBuilder();
		int count = 0;
		
		while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		}
		System.out.print(output);
		scan.close();
	}

} Main public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		StringBuilder output = new StringBuilder();
		int count = 0;
		
		while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		}
		System.out.print(output);
		scan.close();
	} main {
		Scanner scan = new Scanner(System.in);
		StringBuilder output = new StringBuilder();
		int count = 0;
		
		while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		}
		System.out.print(output);
		scan.close();
	} Scanner scan = new Scanner(System.in); scan new Scanner(System.in) StringBuilder output = new StringBuilder(); output new StringBuilder() int count = 0; count 0 while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		} true {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		} int n = scan.nextInt(); n scan.nextInt() scan.nextInt scan int x = scan.nextInt(); x scan.nextInt() scan.nextInt scan if (n == 0 && x == 0) break; n == 0 && x == 0 n == 0 n 0 x == 0 x 0 break; for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; 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 i n i++ i++ i {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			} {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			} for (int j = i+1; j <= n; 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 j n 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 output.append(count).append('\n') output.append(count).append output.append(count) output.append output count '\n' count = 0 count 0 System.out.print(output) System.out.print System.out System System.out output scan.close() scan.close scan String[] args args public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		StringBuilder output = new StringBuilder();
		int count = 0;
		
		while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		}
		System.out.print(output);
		scan.close();
	}

} public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		StringBuilder output = new StringBuilder();
		int count = 0;
		
		while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		}
		System.out.print(output);
		scan.close();
	}

} Main
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		StringBuilder output = new StringBuilder();
		int count = 0;
		
		while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			
			if (n == 0 && x == 0) break;
			
			for (int i = 1; i <= n; i++) {
				for (int j = i+1; j <= n; j++) {
					for (int k = j+1; k <= n; k++) {
						if ((i + j + k) == x)
							count++;
					}
				}
			}
			output.append(count).append('\n');
			count = 0;
		}
		System.out.print(output);
		scan.close();
	}

}