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Guest Message by DevFuse


Member Since 09 Jul 2013
Offline Last Active May 15 2015 12:11 PM

#342043 Simulating an n-sided die with two coins

Posted by gavinksong on 09 April 2015 - 03:09 AM

Say we want to simulate an N sided die.


Spoiler for answer

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#341902 Horizontally randomly moving particle

Posted by gavinksong on 13 March 2015 - 04:30 AM

Spoiler for

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#341901 n!+1 is composite

Posted by gavinksong on 13 March 2015 - 04:23 AM

"Composite" refers to the number having at least two distinct positive integer divisors.


Actually, that's not quite true as 1 is also a positive integer divisor.

Composite really just means "not prime".

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#341885 Orange square

Posted by gavinksong on 12 March 2015 - 01:13 PM

"I'm getting quite a collection of bonanova stars. (emoticon with big grin)



Well, if you don't toot your own horn, others probably won't come along and do it for you.


Someone should send you some ointment to put on your back where you have been frequently patting it.


My sincerest apologies to Perhaps check it again for offending his fragile sensibilities. My colon-D resulted in a goofier-looking grin than I had intended. In the future, I will make a better effort to contain my raging inner narcissist.


As a token of apology, I'd like to share some of my ointment with Perhaps check it again as he has no doubt developed some of his own abrasions after making that devastatingly witty comment of his.

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#341879 Orange square

Posted by gavinksong on 11 March 2015 - 02:43 PM

I'm getting quite a collection of bonanova stars. :D

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#341583 The Price of Wine

Posted by gavinksong on 15 February 2015 - 08:00 PM

Spoiler for


Close, but TSLF said that there can be only one bottle in each pan.

I'm going to have to steal the correct answer from you. ;)


Spoiler for

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#340729 Retirement

Posted by gavinksong on 23 October 2014 - 12:25 PM

Spoiler for One key to this puzzle is that a person does not necessarily apply for a bus pass the day they reach the retirement age.

This is incorrect because the minimum requirement only advances three months at a time. It does not suddenly jump forward by a year.

Spoiler for

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#340728 Pecular Spectra

Posted by gavinksong on 23 October 2014 - 12:19 PM

Spoiler for answer

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#340726 Pecular Spectra

Posted by gavinksong on 23 October 2014 - 11:13 AM

Oh wait.
Spoiler for

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#340609 Upside Down Cake

Posted by gavinksong on 16 October 2014 - 05:27 PM

(This puzzle is from a blog called By Way Of Contradiction.)

Imagine you have a circular cake, that is frosted on the top. You cut a d degree slice out of it, and then put it back, but rotated so that it is upside down. Now, d degrees of the cake have frosting on the bottom, while 360 minus d degrees have frosting on the top. Rotate the cake d degrees, take the next slice, and put it upside down. Now, assuming the d is less than 180, 2d degrees of the cake will have frosting on the bottom.

If d is 60 degrees, then after you repeat this procedure, flipping a single slice and rotating 6 times, all the frosting will be on the bottom. If you repeat the procedure 12 times, all of the frosting will be back on the top of the cake.

For what values of d does the cake eventually get back to having all the frosting on the top?
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#334139 Creative Paradox

Posted by gavinksong on 13 July 2013 - 12:08 PM

This also reminds me of this (Concave and Convex by MC Escher):


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