In the early 1990s, Solipsys Limited was founded to cover a range of various activities. Over time these have evolved primarily into a selection of talks and workshops covering a range of mathematical ideas.
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I've dealt with any number of technically brilliant people who produce outstanding work. The majority of them never bothered to write down their work and communicate it to others - report writing is too boring, uninteresting, and hard. And irrelevant. Or so they thought.
I've dealt with any number of technically brilliant people who produce outstanding work. The majority of them never bothered to write down their work and communicate it to others - report writing is too boring, uninteresting, and hard. And irrelevant. Or so they thought.
Gosper's Glider Gun in Conway's Game of Life I'd known of Conway since my early teens. I remember reading about his Game of Life in an old Scientific American someone gave me. The article (a quick search tells me) was published in October 1970, so I'm guessing I saw it in the early 70s, perhaps 1972. I was hooked.
This post is not about that story. This post is about a comment made by one of the readers in the forum where I saw it.
Oh, and - added later - the original from PG is undated, but the "enhanced" version below it was on the C2 wiki in 2003/2004 and possibly earlier, so don't for one minute think it's supposed to be up-to-date, or refer to modern version of these languages.
Some time ago I gave a talk in which I showed that something unexpected happened with a deck of playing cards. I had some volunteers try it, and while they did so I talked about just how many orderings there are for 52 cards. I computed (an approximation to) $52!$ (52 factorial) by hand. It's not so hard - you just…
I'm receiving lots of recommendations via the HN item, I will need to vet and categorise them, but they are mostly looking great. Here, unvetted and uncategorised are some:
One of my favourite Limited Audience Jokes (although technically it's actually a riddle) goes:
This is a new thing for me - I'm hosting a blog post by a colleague/friend - James Tanton. You can find James' original post here. One reason it's being re-hosted here is because Medium is apparently blocked in some countries: Egypt Malaysia ..... possibly others. It is astounding to me that mathematics - of all…
This page has been Tagged As Software This is a truism that lots of people quote, but it can be hard to remember, especially in the heat of battle (as it were). Rather fortunately it came to mind just when needed, as I found something completely unexpected.
Slightly surprisingly, I got a reply, in which he suggested that I submit the link to Hacker News[4]. I'd never heard of Hacker News, but had a look, thought it interesting, and submitted the link.
It's incomplete, but probably a reasonable place to start. If you think there's something that desperately need to be fixed then send me email and I'll look at it.
A word of warning ... I'm presenting here something called an analogy. It's not perfect, it has problems, it's not exact, but there are ways in which it can aid your thinking. I'm giving a way of visualising high-dimensional spheres, a way that has its limitations, but which can help avoid making mistakes based on…
During the second World War, fighter pilots would scramble to take off. As they bumbled down the grass runway, engines open at full throttle, trying to take off on a short, bumpy track with a full load of fuel and ammunition, their heart would stop when the engine mis-fired. Was the fuel mix too rich, or too lean?…
One of my favourite Limited Audience Jokes (although technically it's actually a riddle) goes:
Sieve of Eratosthenes animation Source: Wikipedia[0] One of the things we need to do when finding Perrin Pseudo-Primes is to recognise prime numbers so we can see if the numbers predicted by the Perrin test to be prime, are. So we need to generate primes. For small primes (for some definition of "small") this can be…
Recently I've been discussing the details of measuring the size of the Earth by watching a shadow descending a wall at sunrise, or ascending at sunset. The sums are easy enough if you do it at either Equinox, and at the Equator, and you can read about it here:
In Part 2 article I'll describe how I personally would write the code specified in Part 1. I'm not claiming this is in any sense objectively the best, and I'm certainly not suggesting it's the only.
You may feel like you've seen this before. If you have, skip to the end where I talk about a formula, and discuss the relevance to parameters in computer hashing algorithms. In particular, I'm going to talk about how large hash spaces should be to avoid collisions with a given level of probability. If there are just…
I've now stopped accepting new versions, so please don't send me any more. However, there has been such a strong reaction to this that I intend to offer another opportunity for people to write simple code and have it analysed and compared with others.