Talking about the primes...
I have to talk about Abigail's oneliner: 
perl -wle 'print "Prime" if (1 x shift) !~ /^1?$|^(11+?)\1+$/' [num]

[download]

More details on http://montreal.pm.org/tech/neil_kandalgaonkar.shtml
(from google)

Hopes perl -le '$_=$,=q,\,@4O,,s,^$,$\,,s,s,^,b9,s,$_^=q,$\^-]!,,print'

In reply to Re: Testing for prime-ness, the silly way by hopes
in thread Testing for prime-ness, the silly way by Dedalus

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