Find the sum of amicable numbers under 10000

Project Euler problem 21 is to find the sum of all amicable numbers under 10000. An amicable number is:

Let \(d(n)\) be the sum of proper divisors of \(n\) then \(d(a)=b\) and \(d(b)=a\) if \(a!=b\) then \(a\) and \(b\) are amicable numbers.

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Project Euler, Visual Studio and playing with Python

I got Visual Studio 2017 through Microsoft’s Dreamspark promotion and thought I’d give it a try. I haven’t done a lot of development under Windows because its only on my laptop and my Linux desktop has 12 Gb RAM.
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Asus X541S

My wife’s laptop is an Asus X541SA – a fairly generic and inexpensive workhorse. With a Quad-Core N3710, 4Gb of RAM and a 1TB HDD. Unfortunately its ridiculously slow. Opening, switching and closing applications leaves time to make a cup of tea and clicking save in Word is likely to see a “(not responding)” caption in the title bar.

A quick look in task manager shows the HDD is perpetually at 100%. Having already tried a clean install of Windows 10, I figured an SSD might help. I got this 120 Gb SanDisk SSD, having used them before with good results.

What a difference it makes, the laptop is not only usable but responsive. While I doubt it would handle many games it can at least cope with Office and Firefox, which it couldn’t before.

Flashing Nexus 9 factory image

This tablet was super fast when I got it but now it lags and drives me nuts. I’d seen someone post on Reddit that flashing the factory image helped so I gave it a go.

Factory images are available here along with good, clear instructions. One caveat, Arch needs super user for fastboot otherwise you get “< Waiting for device >”. For the same reason run flash-all.sh with sudo too.

As to whether or not it helped, it is hard to say but I feel it has. How do you measure something that is entirely subjective?

Edit. Its been a few days now and it is faster. Much faster and without lag. I’m unclear why though. I’m not completely familiar with Android’s architecture but wonder if it’s a combination of multiple updates being applied (this was I think Android 5.0 when bought) and accumulated futz.

[Insert project title here]

An Android fitness tracker application. Feedback from the preparation forum was positive, there is enough scope to expand or contract the project as needed. Importantly, it is “substantially within the sphere of information technology”.

Taking approaches from IT Systems Planning for Success (TM353) and an Agile approach from Software Engineering (TM354) meets the requirements. There is a substantial part of the application that needs synchronise with a server, utilising another level 3 module Developing Concurrent Distributed Systems (M362).

What I haven’t decided is the title!