20190912, 13:11  #1 
Mar 2018
17×31 Posts 
Is 2^1028379412^102837931 probable prime?
Is 2^1028379412^102837931 probable prime? where  denotes concatenation base 10.

20190912, 13:17  #2 
Bamboozled!
"πΊππ·π·π"
May 2003
Down not across
2×7^{2}×109 Posts 

20190912, 13:37  #3 
Undefined
"The unspeakable one"
Jun 2006
My evil lair
2^{2}·5·307 Posts 
No, no, no. Not like that. Badly worded. The "correct" way to coerce others into running your test for you is to claim that it is a PRP. Even better if you claim to use some dubious numerology to arrive at the conclusion. Then people will be falling other each other to be the first to try and prove you wrong.

20190912, 14:22  #4 
Feb 2017
Nowhere
1000110110100_{2} Posts 
I have no idea how far you have checked for possible small prime factors p. For this purpose, one could of course use the expression
10^3095731*(2^10283794  1) + 2^10283793  1 which can be easily reduced modulo p. If p is really small, it might also be worth reducing the exponents modulo p  1. That's it for me. 
20190912, 14:29  #5 
Romulan Interpreter
Jun 2011
Thailand
2^{5}×5×59 Posts 
yes, it is probable prime with a probability between zero and one.

20190912, 17:06  #6 
Nov 2016
2,819 Posts 

20190913, 06:03  #7 
Mar 2018
17×31 Posts 
not yet found a factor
Pfgw is running with f100
9000000/65000000 the progress not yet found a factor... 
20190913, 07:33  #8 
Mar 2018
17·31 Posts 
i am running a prp test
now i am running a prp test...in 50 days i will finish

20190914, 05:08  #9 
Romulan Interpreter
Jun 2011
Thailand
22340_{8} Posts 

20190916, 07:04  #10 
Mar 2018
1000001111_{2} Posts 
small factors
trial division f100 with Pfgw says that there is no small factor.
What does it mean? The number has no "small" factor below? (10^8, 10^9,10^10)? THE NUMBER IS NOT PRP!!! Last fiddled with by enzocreti on 20191028 at 10:08 
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