Rules

This year, Number Tournament will be hosted in person. Once time is up, participants cannot modify their answers. Participants will be graded by volunteers after the game. 

 

Game Rules

 

Specific rules and details about each game can be viewed through the Games Page.

 

Tiebreaker

In the rare case of a tie, whether it be between individuals or teams, they will be paired up against each other, and will play the target game for three minutes. Whichever side comes up with the most methods of hitting the target will win. In the case of multiple ties, each tiebreaker will eliminate one side, until there is one champion left.

The Fine Print

  • In all games, all given numbers must be used once and only once.

  • Numbers cannot be concatenated to form a multi-digit number. For example, you cannot put together 1 and 2 to make 12.

  • Besides + - x / and (), other well-known functions are also allowed, such as exponent, root, factorial, double factorial, triangular numbers... the sky is the limit! However, defining and using your own functions is disallowed. For example, defining f(x) = 16 with a target of 16 is illegal, for obvious reasons.

  • Triangle numbers and rectangle numbers are allowed. Other shape functions such as pentagon numbers are not.

  • When using exponents or similar functions which take multiple inputs, all function inputs must be either one of the provided numbers or be a result of an expression which follows the above rule.

    • Use 1, 3, 4, 5 to make 24:  5 ^ 2 - 1 x (4 - 3) (Invalid, since 2 is used as an exponent)

    • Use 2, 3, 4, 6 to make 18: 4 ^ (6 / 3) + 2 (Valid)

    • Use 1, 2, 3, 4 to make 5: 4C3 + 2 - 1 (Valid, since C is the well-known choose function, giving 4C3=4)

  • Note that square roots can be done with or without a two. However, cube roots and further roots require the number on upper left of the radical sign.

  • Numbers can be written as a subscript (ex. triangular number) or a superscript (ex. exponent).

  • Dots used to indicate decimals and overline bars used to indicate repeating decimals do not count as functions, and are disallowed.

  • Order of operations is strictly enforced! If you are unsure, use parentheses.

  • If the commutative and associative properties of a function are used to write an expression in two different ways, both methods do not count as distinct. For example, 1 + 2 and 2 + 1 would count as the same method, and (3 x 4) / 2 and (3 / 2) x 4 would also count as the same method. You need to use other operations or other functions to create distinct methods.

  • Functions or recursive functions that take one input and result in the same value does NOT count as another way. Ex. 1 + 2, sqrt(1) + 2, 1 + 2! and 1 + (2!)! do not count as distinct methods since the square root and factorial do not change the input; but 5 x 1 and 5 / 1 count as distinct methods because different operations are used. 

*In the event of ambiguity or dispute, the board of judges has the final say.