DejMar

@plasmid, With the givens, I do not believe {2, 2Π, 4 - Π} satisfy the three reals.

I wish to clarify two things: One, when you say "concatenation is not allowed", does that apply to the factorial signs? That is, does the rule eliminate the double factorial? Two, is this rule modification correct? "An expression isn't valid unless if at least one operation, or set of parentheses, or both can be removed, and the expression is still equal to 24." At a quick initial read I expected it was trying to eliminate solutions that are basically identical due to the communitive property of some mathematical operations, such as X+Y is basically the same as Y+X, and perhaps the associative property, such as X+(Y+Z) = (X+Y)+Z. Yet, a second and more thorough read it basically states that the solution must be enclosed within another solution or an additonal set of parentheses are required. This interpretation seems odd, thus the request for clarification.

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