import java.util.ArrayList;
import java.util.Arrays;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (true) {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        }
    }
} import java.util.ArrayList; ArrayList java.util import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (true) {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        }
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (true) {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        }
    } main {
        Scanner scanner = new Scanner(System.in);

        while (true) {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        }
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) while (true) {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        } true {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        } int n = scanner.nextInt() n scanner.nextInt() scanner.nextInt scanner 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; int count = 0; count 0 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 System.out.println(count) System.out.println System.out System System.out count String[] args args public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (true) {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        }
    }
} public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (true) {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        }
    }
} Main
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (true) {
            int n = scanner.nextInt(), x = scanner.nextInt();

            if (n == 0 && x == 0) break;

            int count = 0;
            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++;
                    }
                }
            }
            System.out.println(count);
        }
    }
}
