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From: Dr J R Stockton <reply1600@merlyn.demon.co.uk.invalid>
Newsgroups: comp.lang.javascript
Subject: Re: Primality sieve challenge
Date: Thu, 21 Jan 2016 23:20:38 +0000
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In comp.lang.javascript message <n7k49m$54l$1@news.albasani.net>, Tue,
19 Jan 2016 02:42:13, Stefan Weiss <krewecherl@gmail.com> posted:

>
>A common estimate for the number of atoms in the observable universe is
>10^80. That's a number with ~80 digits. You're going for a number with
>17425170 digits. The raw decimal number takes ~17MB to store in an
>uncompressed ASCII file, like you're proposing. If you were to print it
>out, you'd need around 4k-5k sheets of paper (pages).

<g>
That shows the importance of optimising the base.  One would only need
about 5/6 as many digits in ordinary Hex.  In binary, one would need 3.3
times as many digits; but each digit could be compressed on the paper to
a single black or white pixel, and one could do even better with
coloured pixels.  I estimate that a really good inkjet printer might get
the whole lot onto a single sheet of paper.
</g>

Via the Wayback Machine, http://www.merlyn.demon.co.uk/js-misc0.htm has
JavaScript code for Sieves of Eratosthenes.

-- 
 (c) John Stockton, Surrey, UK.  ¬@merlyn.demon.co.uk   Turnpike v6.05   MIME.
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