• Recent Factors
|Jul 29, 2016|
|11 • 2992 - 1||c211
||154511797545112540590562579413194951963713169<p45> • |
|3 • 2758 + 1||c228
||36729110636284214414023465325820243732150982857931<p50> • |
|Jul 23, 2016|
|15 • 2886 + 1||c211
||21577815855225811689201577313666389932167<p41> • |
|Jul 22, 2016|
|5 • 2788 + 1||c211
||2794949051411859194000431053383243972993081<p43> • |
|13 • 2878 - 1||c211
||14462600719152977872780170144518522741031543251<p47> • |
Alternate Web-page Style
Here is a mirror of this web-site, but in a parallel universe
using black text on a pale background.
Using exponents up to 30,000, primes of the form k • 2n ± 1 were calculated using
the latest version of the free OPENpfgw program available from
More photos have been added. See our friend Bill G and a "floating ship"
which appears to hang suspended above the horizon.
Windows 10 and 7
See screen-shots of various Insider Builds of Windows 10.
See some screen-shots of Windows 7.
The latest addition is an Unscramble program to solve Jumble™
The Sydney PC User Group is an independent club of users discussing
all aspects of personal computers.
The members also help each other solve
computer problems. It has several Special Interest Groups or
SIGs including Genealogy, Digital Photography and Web Design.
This web-page was initially written with
one of the programs used by the Web Design SIG. See the
for recent meeting information.
More recently I've written some Perl scripts to construct web-pages based
on tables of integer factors that I have discovered.
Use the inbuilt DOS ftp command to upload files
quickly from a batch file. If uploading different files each time,
however, use a Windows FTP program like the free
Read the details in this short
See what soft hyphens are all about. Enable
test page. We check the Windows version of
Apple's Safari browser.
Unicodes may be necessary in HTML when named
symbols are not available (for
Cyrillic characters Я and и for
Check that you have valid HTML or XHTML code online
using the World Wide Web Consortium (W3C)
official site or offline using the free
CSE HTML Validator Lite
A 112-digit personal
record prime factor has been found on
April 1st, 2016. It divides the 226-digit
number 7 • 2746 + 1 = p112 • p114.
Work is progressing on factorising numbers of the form
k • 2n ± 1
with k (odd) from 3 to 15 and n ≤ 1000. The results are
Msieve, written by Jason Papadopoulos is described. It contains
fast code to solve large sets of linear equations. See the new
to automate Msieve post-processing after a GGNFS
• World Record Factorization (p146 • p156) NEW
Sample CSS shapes.
Updated: Fri Jul 29, 2016
© 2016 Bob Backstrom