while True:

    (n, x) =  [int(i) for i in input().split()]

    if n == x == 0:

        break



    count = 0

    for a in range(1, n+1):

        for b in range(a+1, n+1):

            for c in range(b+1, n+1):

                if (a + b + c) == x:

                    count += 1

    print(count)
while True:

    (n, x) =  [int(i) for i in input().split()]

    if n == x == 0:

        break



    count = 0

    for a in range(1, n+1):

        for b in range(a+1, n+1):

            for c in range(b+1, n+1):

                if (a + b + c) == x:

                    count += 1

                elif (a + b + c) > x:

                    break

    print(count)
while True:
    (n, x) = [int(i) for i in input().split()]
    if n == x == 0:
        break
    count = 0
    for a in range(1, n + 1):
        for b in range(a + 1, n + 1):
            for c in range(b + 1, n + 1):
                if (a + b + c) == x:
                    count += 1
    print(count)

while True:
    (n, x) = [int(i) for i in input().split()]
    if n == x == 0:
        break
    count = 0
    for a in range(1, n + 1):
        for b in range(a + 1, n + 1):
            for c in range(b + 1, n + 1):
                if (a + b + c) == x:
                    count += 1
                elif (a + b + c) > x:
                    break
    print(count)

+                elif (a + b + c) > x: +                    break