You're viewing a comment by Jonas Elfström and its responses.

January 12, 2012, 12:05

Links to other explanations and to a usenet post by Abigail that dates it back to 1997 can be found at my blog.
Abigail's looked like this
perl -wle 'print "Prime" if (1 x shift) !~ /^1?$|^(11+?)\1+$/'

Reply To This Comment

(why do I need your e-mail?)

(Your twitter handle, if you have one.)

Type the word "0day_298": (just to make sure you're a human)

Please preview the comment before submitting to make sure it's OK.