def buttons(n):
    if n<=0:
        return 0
    elif n==7 or n==11:
        return 1
    else:
        return max(buttons(n-7),buttons(n-11))

for i in range(1,100):
    print(i,buttons(i))
    if buttons(i)==0:
        x=i
print('\n')
print("Largest number of buttons that cannot be purchased with packages of 7 and 11: ", x)