Comments for eon http://unimodular.net/blog ecstatic over numbers Thu, 09 Sep 2010 15:23:58 +0000 http://wordpress.org/?v=2.5 Comment on Purse of Denari by Mikael Vejdemo-Johansson http://unimodular.net/blog/?p=190#comment-17821 Mikael Vejdemo-Johansson Thu, 26 Aug 2010 08:22:49 +0000 http://unimodular.net/blog/?p=190#comment-17821 Well, one observation worth making is that it scales. If (a,b,c,d,p) is one solution, then so is (ka,kb,kc,kd,kp). The next observation I have is that Wolfram|Alpha solves the equation system you get by just writing it all down with variables pretty straight-forwardly. Well, one observation worth making is that it scales. If (a,b,c,d,p) is one solution, then so is (ka,kb,kc,kd,kp).

The next observation I have is that Wolfram|Alpha solves the equation system you get by just writing it all down with variables pretty straight-forwardly.

]]> Comment on Charles Dodgson by JoseBrox http://unimodular.net/blog/?p=179#comment-17566 JoseBrox Fri, 30 Jul 2010 20:31:24 +0000 http://unimodular.net/blog/?p=179#comment-17566 That joke/made-story about Carroll is indeed funny! :D That joke/made-story about Carroll is indeed funny! :D

]]> Comment on Number Crunch by tpc http://unimodular.net/blog/?p=170#comment-17102 tpc Tue, 01 Jun 2010 07:35:40 +0000 http://unimodular.net/blog/?p=170#comment-17102 No, I don't think the Australian puts up the daily puzzle on the web. Il'm guessing it's pretty easy to generate puzzles of this kind. Start with a permutation of 1-9 on a 3x3 grid. Randomly insert operators and then compute the numbers in the bottom row and rightmost column. Unlike Sudoku, one don't really need to ensure the solver can solve the puzzle logically. No, I don’t think the Australian puts up the daily puzzle on the web. Il’m guessing it’s pretty easy to generate puzzles of this kind. Start with a permutation of 1-9 on a 3×3 grid. Randomly insert operators and then compute the numbers in the bottom row and rightmost column. Unlike Sudoku, one don’t really need to ensure the solver can solve the puzzle logically.

]]> Comment on Number Crunch by laogui32 http://unimodular.net/blog/?p=170#comment-17100 laogui32 Mon, 31 May 2010 23:10:50 +0000 http://unimodular.net/blog/?p=170#comment-17100 I note some of the Sudoku techniques apply (not surprising since it is another exact cover problem) eg the 2by2 grid (which I noticed in the Australian May 26 and 3x3 grid of course. Also forced pairs and trips etc Do you happen to have a web link to more of these puzzles? I note some of the Sudoku techniques apply (not surprising since it is another exact cover problem) eg the 2by2 grid (which I noticed in the Australian May 26 and 3×3 grid of course. Also forced pairs and trips etc

Do you happen to have a web link to more of these puzzles?

]]> Comment on I heart google translate by John http://unimodular.net/blog/?p=166#comment-16388 John Thu, 11 Mar 2010 00:04:17 +0000 http://unimodular.net/blog/?p=166#comment-16388 Google beat Yahoo hands down on this one. Yahoo produced nonsense such as "the smelly spicy jiao raccoon dog." Google beat Yahoo hands down on this one. Yahoo produced nonsense such as “the smelly spicy jiao raccoon dog.”

]]> Comment on What’s in a name … by John http://unimodular.net/blog/?p=164#comment-16320 John Sun, 28 Feb 2010 00:52:22 +0000 http://unimodular.net/blog/?p=164#comment-16320 To make things more complicated, the <em>last</em> author position is sometimes distinguished in a paper with many authors. Often the last author is the director of the lab that produced the paper. So prestige decreases as you go down the author list until it spikes back up at the end. To make things more complicated, the last author position is sometimes distinguished in a paper with many authors. Often the last author is the director of the lab that produced the paper. So prestige decreases as you go down the author list until it spikes back up at the end.

]]> Comment on Erdös Number by Erd&#246s Lap Number » eon http://unimodular.net/blog/?p=56#comment-14679 Erd&#246s Lap Number » eon Sat, 20 Jun 2009 03:23:14 +0000 http://unimodular.net/blog/?p=56#comment-14679 [...] my Erd&#246s number is still 4. I probably could decrease it to 3 by randomly putting my thesis advisor’s thesis [...] […] my Erd&#246s number is still 4. I probably could decrease it to 3 by randomly putting my thesis advisor’s thesis […]

]]> Comment on A combinatorial identity by tpc http://unimodular.net/blog/?p=147#comment-14255 tpc Tue, 24 Mar 2009 00:59:40 +0000 http://unimodular.net/blog/?p=147#comment-14255 Thanks Brent. That was neat. Thanks Brent. That was neat.

]]> Comment on A combinatorial identity by Brent Yorgey http://unimodular.net/blog/?p=147#comment-14254 Brent Yorgey Mon, 23 Mar 2009 22:14:06 +0000 http://unimodular.net/blog/?p=147#comment-14254 One combinatorial interpretation is as follows: if you are picking (k 1) out of m items, given some ordering of the m items you can break your choices up into disjoint cases based on how many of the items you pass up before choosing the first. After choosing the jth item (and passing up the first j-1) you have exactly (m - j) \choose k ways to choose the rest. One combinatorial interpretation is as follows: if you are picking (k 1) out of m items, given some ordering of the m items you can break your choices up into disjoint cases based on how many of the items you pass up before choosing the first. After choosing the jth item (and passing up the first j-1) you have exactly (m - j) \choose k ways to choose the rest.

]]> Comment on Euler’s Rotation theorem in 3D by Websites tagged "euler" on Postsaver http://unimodular.net/blog/?p=134#comment-14051 Websites tagged "euler" on Postsaver Sun, 01 Feb 2009 22:17:26 +0000 http://unimodular.net/blog/?p=134#comment-14051 [...] - Improving Euler’s Method for Numerical Solutions of Ordinary ... saved by MewSoul2009-01-22 - Euler’s Rotation theorem in 3D saved by TheComedySupplier2009-01-17 - Project Euler - Problem 1 saved by justkidding192009-01-15 - [...] […] - Improving Euler’s Method for Numerical Solutions of Ordinary … saved by MewSoul2009-01-22 - Euler’s Rotation theorem in 3D saved by TheComedySupplier2009-01-17 - Project Euler - Problem 1 saved by justkidding192009-01-15 - […]

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