July 2010
Find a natural number n for which the expression round((1+2cos(20o))n) is divisible by 1,000,000,000.
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Challenge:
07/01/2010 @ 11:14 AM EST
Solution:
08/01/2010 @ 11:14 AM EST
List Updated:
07/01/2010 @ 11:14 AM EST
People who answered correctly:
Michael Brand (07/02/2010 07:00 AM EDT)
Lachezar Hristov (07/02/2010 11:27 AM EDT)
Sergei Agievich (07/03/2010 09:20 AM EDT)
Henry Shin (07/04/2010 11:50 AM EDT)
Albert Stadler (07/05/2010 03:29 AM EDT)
Danny Antonetti & Dan Ignatoff (07/05/2010 08:29 PM EDT)
Harald Bögeholz (07/06/2010 04:59 PM EDT)
Erick Wong (07/06/2010 07:40 PM EDT)
Tomas Sirgedas (07/06/2010 09:41 PM EDT)
Christian Blatter (07/08/2010 03:37 PM EDT)
Daniel Bitin (07/10/2010 01:49 PM EDT)
Jan Fricke (07/12/2010 09:51 AM EDT)
Tim Lewis (07/12/2010 07:42 PM EDT)
Itsik Horovitz (07/13/2010 10:00 AM EDT)
Casey Mihaloew (07/13/2010 10:47 AM EDT)
Andreas Knappe (07/13/2010 03:49 PM EDT)
John T. Robinson (7/13/2010 06:28 PM EDT)
Erik Bernhardsson (07/14/2010 08:19 AM EDT)
Arthur Breitman (07/14/2010 11:05 AM EDT)
Renato Fonseca (07/14/2010 10:32 PM EDT)
Joseph DeVincentis (07/15/2010 02:39 PM EDT)
Yuval Dor (07/16/2010 09:12 AM EDT)
Chris Shannon (07/16/2010 07:52 PM EDT)
Ehud Schreiber (07/20/2010 06:02 AM EDT)
Arun Sivaramakrishnan (07/22/2010 09:27 AM EDT)
Andrew Buchanan (07/24/2010 08:01 AM EDT)
Kurt Hectic (07/28/2010 09:30 AM EDT)
Mitch Schwartz (07/28/2010 12:49 AM EDT)
Dan Dima (07/30/2010 11:25 AM EDT)
David Shavitt & Julian Gilbey (07/30/2010 12:37 AM EDT)
Andrew Marut (07/30/2010 08:20 PM EDT)
Antonio García Astudillo (07/31/2010 06:37 PM EDT)
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