mersenneforum.org Some special factorization status of generalized repunits
 Register FAQ Search Today's Posts Mark Forums Read

 2020-10-15, 22:11 #1 sweety439     Nov 2016 22×19×31 Posts Some special factorization status of generalized repunits The generalized repunits (b^p-1)/(b-1) with a given factorization status A = Semiprime and divisible by 2*p+1 B = Semiprime and the two prime factors are both large ((number of digits of the larger prime) / (number of digits of the smaller prime) < 1.3) C = The largest two prime factors are very close ((the larger prime) / (the smaller prime) < 100) Code: Base A B C 2 11, 23, 83, 131, 3359 67 (a little > 1.3), 101, 137, 149, 523, 727, 1061, 1277? 277 (a little > 100), 397 (all of the largest three prime factors) 3 11, 23, 131 349, 661 (a little > 1.3) 569 6 11 67, 353 347 10 (none known) 17 (a little > 1.3), 71, 211 193, 223 12 131 311? 23, 193, 239

 Similar Threads Thread Thread Starter Forum Replies Last Post MrRepunit GPU Computing 24 2020-09-20 20:13 Alberico Lepore Alberico Lepore 1 2020-05-27 12:20 sweety439 And now for something completely different 1 2016-12-07 15:58 ProximaCentauri Miscellaneous Math 9 2014-12-05 19:06 NBtarheel_33 Puzzles 32 2013-09-10 17:37

All times are UTC. The time now is 01:01.

Sat Oct 24 01:01:08 UTC 2020 up 43 days, 22:12, 0 users, load averages: 0.95, 1.12, 1.17