I have no idea who it was that originally came up with the idea of regexes, but I liked it and it seems appropriate here, so:

#!perl -p
$_ x=(1x$_)!~/^(|.|(..+)\2+)$/

[download]
$ seq -50 50 | perl prime.pl
2
3
5
7
11
13
17
19
23
29
31
37
41
43
47

[download]

In reply to Re: Prime number generator by truedfx
in thread Prime number generator by jimt

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