BrowserUk,
What if that was sum 1 .. 2**30;? 
use Math::BigInt;

my $sum = Math::BigInt->new(2);
$sum->bpow(30);
$sum = ($sum * $sum + $sum) / 2;
print $sum;
__DATA__
576460752840294400

[download]
This is mostly in jest but it does illustrate that programmer knowledge of the specific task at hand is more valuable then generalizations. There are similar formulas for summing just the odd or even numbers from 1 .. N as well.

Cheers - L~R

In reply to Re^3: &1 is no faster than %2 when checking for oddness. Oh well. by Limbic~Region
in thread &1 is no faster than %2 when checking for oddness. Oh well. by diotalevi

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