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View:  Topic list, Topic summary Topics 1 - 10 of 11014  Older »

the Problem of Apollonius:Calculating (x,y,r) of eight circles given 3 circles 
  Hi - Is it possible to calculate the (x,y) co-ordinates and the radius of each of the eight circles, given three circles of known position and radius? original 3 circles: (ax1,ay1,ar1) (ax2,ay2,ar2) (ax3,ay3,ar3) solutions: (sx1,sy1,sr1) (sx2,sy2,sr2) etc does it help to assume all 3 circles are in the 1st quadrant?... more »
By BookWight  - May 12 - 5 new of 5 messages    

P2P Share files by email on Thu 04/25/2013 
  Do you think that Peer-to-Peer, FTP IRC technologies etc...are too much complicated !? There is a simpler technology to use, Autosend. This software allows file-sharing by only using your e-mail account. Autosend allows sharing files on your computer through regular email. It is an automatic file mailer... more »
By share.files...@email.con  - Apr 25 - 1 new of 1 message    

Card Magic and My Mathematical Discoveries 
  Hi I just published my first ebook titled “Card Magic and My Mathematical Discoveries” The book is an excellent mathematics resource for both performing art and implicit mathematics teaching. Moreover, the book is not only about card magic but it is also loaded with riddles, mathematical amusement and mind-blowing mathematical discoveries characterized by logical intelligence.... more »
By alexiomatics  - Apr 25 - 1 new of 1 message    

Math puzzle 
  From high school days, some genuine recreational math: A math professor was talking with his assistant. "Yesterday I met three people," said the professor. "When you multiply their ages together, you get 2450. When you add their ages together, it adds up to twice your age. What are their ages?"... more »
By JMF  - Apr 24 - 4 new of 4 messages    

Children's Story Book to Introduce Set Theory, Order Theory 
  My wife and I are having out first child and I'd like to make sure it is properly inundated with science and math as the backdrop for its life. I've been recently learning about set theory and order theory myself, and had the idea to introduce some of the basic concepts subtly through a children's story book. I'm reaching out to the folks on this list for ideas on how to do this.... more »
By mearn...@gmail.com  - Apr 23 - 3 new of 3 messages    

primes in the arithmetic sequence 1, 31, 61, 91, 121, ... 30k+1 ... 
  I was looking for a simple arithmetic sequence with many primes "crowded together", i.e. quasi-consecutive ... Suppose we let n = 1,097,495,500,000 ; then I get this: n+19941 is prime, n+19971 is prime, n+20001 is prime, n+20031 is prime, n+20061 is prime, n+20091 is prime, n+20121 is composite,... more »
By David Bernier  - Apr 22 - 6 new of 6 messages    

flashlight following path traced out by Peano-type curve, Kakeya needle problem 
  The 2D Kakeya needle problem asks how "small" a compact set K in R^2 can be if K contains a unit length line segment [A, B] in every direction in the plane. The smallness can be evaluated by the Lebesgue measure of K, or some finer notion of smallness (Hausdorff dimension). For example, with a circle of radius 100 and a point Q... more »
By David Bernier  - Apr 21 - 5 new of 5 messages    

DOW at 14,613.48 .... irrational exuberance? 
  In article <kk4e7m$ks...@dont-email.me>, ... ... Didn't you notice the "...." after it? -- Richard
By Richard Tobin  - Apr 10 - 1 new of 1 message    

Let's give away some goals 
  [link] Close packing. Geometry. Organizers of Brazil 2014 FIFA World Cup want to give away some official balls. We face a close-packing problem in order to know if we can fill Maracana stadium with enough balls to satisfy the Championship organizers' wishes.
By Matifutbol  - Apr 6 - 1 new of 1 message    

AfmToPfm 
  AfmToPfm [link] AV Voice Changer Software [link] 24x24 Free Application Icons [link] 3proxy [link] History Cleaner [link] AfmToPfm
By Archibald theo thi  - Mar 31 - 1 new of 1 message    

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