while True:

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



    if n == x == 0:

        break



    count = 0

    for s in range(1, n - 1):

        for m in range(s + 1, n):

            for e in range(m + 1, n + 1):

                if x == sum([s, m, e]):

                    count += 1



    print(count)
while True:

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



    if n == x == 0:

        break



    count = 0

    for s in range(1, n - 1):

        for m in range(s + 1, n):

            for e in range(m + 1, n + 1):

                if x == s + m + e:

                    count += 1



    print(count)
while True:
    n, x = [int(i) for i in input().split()]
    if n == x == 0:
        break
    count = 0
    for s in range(1, n - 1):
        for m in range(s + 1, n):
            for e in range(m + 1, n + 1):
                if x == sum([s, m, e]):
                    count += 1
    print(count)

while True:
    n, x = [int(i) for i in input().split()]
    if n == x == 0:
        break
    count = 0
    for s in range(1, n - 1):
        for m in range(s + 1, n):
            for e in range(m + 1, n + 1):
                if x == s + m + e:
                    count += 1
    print(count)

-                if x == sum([s, m, e]): +                if x == s + m + e: