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|The five 3īs (Posted on 2008-07-07)
This is a real story. A long long time ago, based on the "Four fours" problem, I wondered if I could do the same using exactly five 3īs, the restrictions a bit tighter: I could use only the 4 basic math operations, exponentiation, factorial, and all parentheses I may need. Besides, I didnīt disallow me to join two "3īs" to make "33".
Using this, and only this, I succeeded in writing expressions for all integers from 0 to 100.
To narrow your work, since a great number of integers can be easily obtained, can you find expressions for 47, 50, 56, 58, 64, 70, 71, 73, 74, 76, 77, 85, 88, 94, and 95?
re(3): all hundred
| Comment 30 of 35 |
(In reply to re(2): all hundred
by Dej Mar)
> Leming, you trying to see how many you can get?
Yes (and no). Yes I was, but after seeing your post, I realize my semi-brute-force method only allowed integers in intermediate steps.
(3!)!/(3^3) = 720/27 is not one of the possibilities under my approach.
Not sure I want to start from scratch to find out what is the smallest integer that cannot be obtained.
Posted by Leming
on 2008-07-09 09:53:15
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