import java.util.Scanner;

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

        while(sc.hasNext()){
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        }

    }
}
 import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        while(sc.hasNext()){
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        }

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

        while(sc.hasNext()){
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        }

    } main {
        Scanner sc = new Scanner(System.in);

        while(sc.hasNext()){
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        }

    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) while(sc.hasNext()){
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        } sc.hasNext() sc.hasNext sc {
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        } int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int x = sc.nextInt(); x sc.nextInt() sc.nextInt sc int count=0; count 0 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 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 sc = new Scanner(System.in);

        while(sc.hasNext()){
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        }

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

        while(sc.hasNext()){
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        }

    }
} Main
import java.util.Scanner;

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

        while(sc.hasNext()){
            int n = sc.nextInt();
            int x = sc.nextInt();
            int count=0;

            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++;
                    }
                }
            }
            System.out.println(count);
        }

    }
}

