AMDave
12-18-2013, 10:51 AM
First base 5 mega prime found!
On 4 December 2013, 20:53:51 UTC, PrimeGrid’s Sierpinski/Riesel Base 5 Problem project eliminated k=173198 by finding the mega prime: 173198*5^1457792-1 (http://primes.utm.edu/primes/page.php?id=116553) The prime is 1,018,959 digits long and enters Chris Caldwell's The Largest Known Primes Database (http://primes.utm.edu/primes) ranked 67th overall. This is the first known base 5 mega prime. 88 k's now remain in the Riesel Base 5 Problem. The discovery was made by Motohiro Ohno (syusui (http://www.primegrid.com/show_user.php?userid=77758)) of Japan using an Intel(R) Core(TM) i3-2120 CPU @ 3.30GHz with 4GB RAM running Microsoft Windows 7 Home Premium. This computer took about 22 hours and 29 minutes to complete the primality test using LLR. Motohiro is a member of the Team 2ch (http://www.primegrid.com/team_display.php?teamid=194) team. The prime was verified on 6 December 2013 5:27:38 UTC, by Scott Brown (Scott Brown (http://www.primegrid.com/show_user.php?userid=1178)) of the United States using an Intel(R) Core(TM) i7-2600 CPU @ 3.40GHz with 8 GB RAM running Microsoft Windows 7 Home Premium. This computer took about 33 hours and 22 minutes to complete the primality test using LLR. Scott is a member of the Duke University (http://www.primegrid.com/team_display.php?teamid=154) team. For more details, please see the official announcement (http://www.primegrid.com/download/SR5-173198.pdf).
More... (http://www.primegrid.com/forum_thread.php?id=5399)
On 4 December 2013, 20:53:51 UTC, PrimeGrid’s Sierpinski/Riesel Base 5 Problem project eliminated k=173198 by finding the mega prime: 173198*5^1457792-1 (http://primes.utm.edu/primes/page.php?id=116553) The prime is 1,018,959 digits long and enters Chris Caldwell's The Largest Known Primes Database (http://primes.utm.edu/primes) ranked 67th overall. This is the first known base 5 mega prime. 88 k's now remain in the Riesel Base 5 Problem. The discovery was made by Motohiro Ohno (syusui (http://www.primegrid.com/show_user.php?userid=77758)) of Japan using an Intel(R) Core(TM) i3-2120 CPU @ 3.30GHz with 4GB RAM running Microsoft Windows 7 Home Premium. This computer took about 22 hours and 29 minutes to complete the primality test using LLR. Motohiro is a member of the Team 2ch (http://www.primegrid.com/team_display.php?teamid=194) team. The prime was verified on 6 December 2013 5:27:38 UTC, by Scott Brown (Scott Brown (http://www.primegrid.com/show_user.php?userid=1178)) of the United States using an Intel(R) Core(TM) i7-2600 CPU @ 3.40GHz with 8 GB RAM running Microsoft Windows 7 Home Premium. This computer took about 33 hours and 22 minutes to complete the primality test using LLR. Scott is a member of the Duke University (http://www.primegrid.com/team_display.php?teamid=154) team. For more details, please see the official announcement (http://www.primegrid.com/download/SR5-173198.pdf).
More... (http://www.primegrid.com/forum_thread.php?id=5399)