Introduction

This is a personal website.
Its aim is to find some factors of somewhat larger numbers,
which are taken from the database of Markus Tervooren
and where any result is uploaded to.


Numbers of the form 10^n + 1

Finds in 2023: 6583 factors of 5752 numbers (Dec 28, 2023).
The largest factor is p42 = 713179443752745679211641547767533209753303 of 10^839 + 1.

(10^183917+1)/11/9952852373 is a probable prime with 183906 digits (February 9, 2024).

(10^313741+1)/11/11294677 is a probable prime with 313733 digits (April 15, 2024).


Numbers of the form 10^n − 1

Finds in 2023: 2389 factors of 2305 numbers (Dec 28, 2023).
The largest factor is p55 = 2862577930401391395910619889316394633711512313018581507 of 10^1599 − 1.


Proven primes (related to numbers of the forms 10^n ± 1)

For a large number it is not easy to determine wether it is prime or composite.
Marcel Martin wrote the program primo which can prove (or disprove) the primality of a number.
In a few cases I used it to create a certificate (Dec 25, 2023).


April 15, 2024

Alfred Reich