Joseph Herlant
version 1.0.0, 2013-10-25 : Initial version

The look-and-say mathematical sequence has been introduced and analyzed by John Conway. If you don’t know this sequence, look at the explanations given on Wikipedia. It is also konw as the Conway Sequence.

This one-liner calculates the sequence until the member length is 64 or more. If you want to change this, change the "64" at the end of the line.

perl -le '$_=1;print&&s/((\d)\2*)/length($1).$2/ge while length()<64'

Here is the output of the oneliner:

1
11
21
1211
111221
312211
13112221
1113213211
31131211131221
13211311123113112211
11131221133112132113212221
3113112221232112111312211312113211
1321132132111213122112311311222113111221131221
11131221131211131231121113112221121321132132211331222113112211