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Guest Message by DevFuse


Member Since --
Offline Last Active May 13 2015 10:28 AM

Posts I've Made

In Topic: Relatively prime

05 May 2015 - 01:32 PM

Most of you got it.
BMAD made a close estimate of the probability, which is actually just slightly greater than 60% to be co-prime.
I'm marking her answer, therefore.


Just for fun, I programmed up a little script. Using a suitable underlying GMP library for Euler's totient function, it checked up to 10 million in 13 seconds, with a result of 60.793% distinct pairs relatively prime.

In Topic: dice problem

10 April 2015 - 11:51 AM


you want to throw three 8 sided dice; such that: all three dice are numbered the same, and 120 different totals are possible; and the maximum number is as small as possible.

with 7 sided dice, the best possible is: 1, 2, 8, 51, 60, 79, 83

but your challenge is to go one more side.

Maximum sum, or highest numbered side?


Spoiler for Factoring

In Topic: dice problem

08 April 2015 - 03:42 PM

Spoiler for Interesting approach found elsewhere

In Topic: Conditionally conflicting

06 February 2015 - 05:48 PM

Spoiler for Perl:

In Topic: The army of ants

14 August 2014 - 04:30 PM

I saw this puzzle in the same Peter Winkler book I mentioned elsewhere.

Spoiler for Here's what I think