preethi has 6 flavors of ice cream in his parlor . how many options are there for dorathy to pick a one - flavor , two - flavor , 3 - flavor , 4 - flavor , 5 flavor or 6 flavor order ?
6 c 1 + 6 c 2 + 6 c 3 + 6 c 4 + 6 c 5 + 6 c 6 = 63 . answer : e
add(add(add(add(divide(factorial(6), factorial(5)), divide(factorial(6), multiply(const_2, factorial(4)))), divide(factorial(6), multiply(factorial(3), factorial(3)))), divide(factorial(6), multiply(const_2, factorial(4)))), divide(factorial(6), factorial(5)))