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Guest Message by DevFuse


Member Since 30 Jul 2012
Offline Last Active Yesterday, 10:25 PM

#341914 n!+1 is composite

Posted by Rainman on 13 March 2015 - 12:09 PM

Spoiler for

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#341913 Apple, blueberry or pumpkin?

Posted by Rainman on 13 March 2015 - 11:51 AM

Spoiler for

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#341796 The professor's son.

Posted by Rainman on 03 March 2015 - 11:39 PM


Spoiler for


Spoiler for minor correction


Spoiler for my bad

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#341795 Checkerboard Challenge

Posted by Rainman on 03 March 2015 - 11:30 PM

Spoiler for

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#341696 A mean, mean minimization problem

Posted by Rainman on 25 February 2015 - 05:45 PM

Spoiler for

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#341584 Hello guys i have a puzzle/riddle i can not work out

Posted by Rainman on 16 February 2015 - 02:17 AM

Spoiler for

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#337280 Inequalities for large integers

Posted by Rainman on 29 January 2014 - 12:49 PM

These problems use Knuth's up-arrow notation (http://en.wikipedia....-arrow_notation), with ^ being the up-arrow.


1. Find the smallest value for n, such that 1000^^n > 12^^(n+1).


2. We define the sequence g, by assigning g(1) = 3^^^^3, and g(n+1) = 3^^^...^3, where the number of up-arrows is g(n). A famously large number is Graham's number = g(64). Which is larger, Graham's number or 2^^^...^2, where the number of up-arrows is Graham's number?

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#336956 Can you decript this?

Posted by Rainman on 09 December 2013 - 11:26 PM

I don't have friends

That sucks, I don't have many friends myself. Aaryan's point, though, is that asking us to solve it for you is cheating. But since you got the hint of using a 9x6 matrix, I'll at least do you the favor of putting the message in a 9x6 matrix.




Hopefully you can see it now. Good luck with the competition!

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#334853 Chase on an endless road, continued

Posted by Rainman on 30 July 2013 - 04:46 PM

Caught again, your friend concedes that you are the supreme runner. Maybe it's not a coincidence that your profile pic is an ostrich ;)

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#327168 piece of cake

Posted by Rainman on 10 January 2013 - 04:44 PM

Spoiler for the cake could look like this

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#326785 Blood runs thick in Transylvania

Posted by Rainman on 19 December 2012 - 05:04 PM

Spoiler for Answer

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#326671 Amoeba evacuation puzzle

Posted by Rainman on 08 December 2012 - 01:18 AM

Yeah I think that is correct, here's why:

Spoiler for


That's the solution I had in mind for the problem, well done. I also enjoyed your javascript implementation of the problem.

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#326621 Amoeba evacuation puzzle

Posted by Rainman on 29 November 2012 - 11:01 PM

An amoeba is sitting on the bottom left square (A1) of a chessboard which extends infinitely upwards and to the right. You can make an amoeba split into two. If an amoeba is split into two, its offspring will take the square directly above and the square directly to the right of the parent amoeba. This vacates the square of the parent amoeba. So your first move, splitting the amoeba on A1, will put one amoeba on A2 and one amoeba on B1. An amoeba can only split if both spaces for its offspring are unoccupied. Your objective is for all the amoebas to evacuate the area A1, A2, A3, B1, B2, B3, C1, and C2. (Squares marked with x in drawing below)

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#325187 What is the missing term of the sequence?

Posted by Rainman on 08 September 2012 - 06:58 PM

Spoiler for

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