Based on a few ideas from the other posts I came up with the following improvement of your 65 character version, squeezing it to 62. (Now all I have to go and read the docs and figure out how it works. :-) The one I was working on (and understand) was in the line of hopes latest post which I reduced down to 64.

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12345678901234567890123456789012345678901234567890123456789012345
#runrig improvement
$#=" %@{[length$a++*$a/2]}g";print$j+1..($j+=++$i),$/for 2..$a
#blakem/hopes/jynx improvement
$;=length$a++*$a/2;map{printf" %$;d",++$,for 2..$_;print$/}2..$a
[download]

Ahhh, Latecomers Advantage. :-)

Yves / DeMerphq
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