Describe and add

[Michele Dondi]

On Thu, 18 Aug 2005, Eric Angelini wrote:

> Could please someone compute and analyse this sequence?
>
> Start with a(1) = 1
> Describe a(1) --> = 11 (one "1")
> Add a(1) to it's description: 1 + 11 = 12
[and so on...]

I can't help with the analysis, and I doubt that anything as simple as 
what is found for the sequence of audioactive elements could be said - but 
I would be happy to be contradicted. However I can help with a quick perl 
script:


#!/usr/bin/perl -l

use strict;
use warnings;
use bigint;

$_=1;
{
     print my $o=$_;
     s/((\d)\2*)/(length $1).$2/ge;
     $_+=$o;
     <>, redo;
}

__END__


Output:

1

12

1124

212338

1211334656

1112213525496172

31221113152327355441607884

1311223113111543352330284851467051780698

111321221321133115142315123621344927293054493947386362638861942616

311312112211131221232115111412131115111213161211243740343033324425294734255535516245454370615560667973830274103732

1321131112212231131122111213122115311411121113311531121113111611122112452629253224272531563339232924322532242625512536355352484547475838465750368051618862646083796870789687941287275044


Michele
-- 
Never attribute to malice that which
can be adequately explained by stupidity
- "Hanlon's Razor"