perplexus.info :: Numbers : Ones only

Ones only (Posted on 2021-07-12)

What is the minimal number of “ones” needed to express the following 6 numbers:

6, 9, 18, 45, 60, 265.

You may use only the following symbols, each symbol up to three times and any quantity of brackets .
+ - / * ^ !
$ Sum of digits.
. Decimal point
Sqrt Square root.
and concatenation (of numbers only)

Sum up the total of ones and publish your answer.
Examples:
37=111/(1+1+1). Scores 6
48=((1+1+1)!)!! Scores 3

List your 6 formulas.

NB: The order of candidate numbers is not by the level of difficulty

No Solution Yet Submitted by Ady TZIDON

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Comments: ( Back to comment list | You must be logged in to post comments.)

re: My candidate solution - may be imprived

| Comment 4 of 8 |

(In reply to My candidate solution - may be imprived by Ady TZIDON)

Subfactorial? Really? That's even more annoying than the double-factorial.

Either you are not using the usual definition of !n or you have a few errors

The table on

https://en.wikipedia.org/wiki/Derangement

gives

!7=1854 so $(!7)=19

!12=176214841 so $(!12)=34

!5=44

Note $(!13)=45

and !6=265

but $(!8)=19

so it is still wrong

So these can be fixed with a slight change of score.

Posted by Jer on 2021-07-14 08:09:27

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