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-   -   13x666=2020 (https://www.mersenneforum.org/showthread.php?t=26229)

 petrw1 2020-11-25 16:00

13x666=2020

In honor of UncWilly's New Math:
[url]https://www.mersenneforum.org/showpost.php?p=564288&postcount=1068[/url]

Find a formula using only 13 and 666 to get 2020.
You can only use +. -, x, /, ^, !, √

1. Find an answer with the fewest numbers (not digits).
2. Find an answer with the same number of each; and the fewest.

For example my first attempt uses 11 numbers.
So its an answer for 1. but not for 2.
666+666+666+13+13-(13+13)/13-(666+666)/666.

 Viliam Furik 2020-11-25 16:30

13*13*13-13*13-(13+13+13+13+13+13+13+13)/13 = 2020

 Viliam Furik 2020-11-25 16:33

[QUOTE=Viliam Furik;564344]13*13*13-13*13-(13+13+13+13+13+13+13+13)/13 = 2020[/QUOTE]

13*(13*13-13)-(13+13+13+13+13+13+13+13)/13 = 2020

13 13's

 petrw1 2020-11-25 17:02

[QUOTE=Viliam Furik;564345]13*(13*13-13)-(13+13+13+13+13+13+13+13)/13 = 2020

13 13's[/QUOTE]

So next I'll expect 666 666s?

 VBCurtis 2020-11-25 17:11

In the spirit of the original formula, solutions should use both 13 and 666.

 Gelly 2020-11-25 17:19

Trivial improvement to the original solution - 10 numbers

666+666+666-(666+666+666+666)/666+13+13

 henryzz 2020-11-25 17:39

Not much of a record but the first to use ^
(13+13+13+13)/13 + (13+13/13)*(13-13/13)^((13+13)/13)

7 of each
(666+666+666+666)/666 + (13+666/666)*(13-13/13)^((13+13)/13)

 matzetoni 2020-11-25 18:51

Trial and error got me down to 9 numbers:

2020 = 666+((13+13)/13)*(666+13-(13+13)/13)

 Ensigm 2020-11-25 19:37

[QUOTE=henryzz;564355]Not much of a record but the first to use ^
(13+13+13+13)/13 + (13+13/13)*(13-13/13)^((13+13)/13)

7 of each
(666+666+666+666)/666 + (13+666/666)*(13-13/13)^((13+13)/13)[/QUOTE]
The second one is really a smooth answer!

 Ensigm 2020-11-25 19:48

((666+666)/666)**(13-(13+13)/13)-13-13-(666+666)/666

6 each.

 Ensigm 2020-11-25 19:52

[C]**[/C] means [C]^[/C]——I was using python as my calculator, as many would have guessed it.

Written with [C]^[/C], my answer would be [QUOTE]((666+666)/666)^(13-(13+13)/13)-13-13-(666+666)/666[/QUOTE]

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