This is mostly just the straight-forward way I'd do it, but I'm posting it because it appears shorter than most of the solutions so far (though, intentionally written more compactly than usual): 

#!/usr/bin/perl -w
use strict;
my $n= (@ARGV,5)[0];
my @s= (((0)x$n,-1)x$n,(-1)x$n,-1);
my @d= (1,$n+1,-1,-$n-1);
my($p,$d,$v)=(-1,0,0);
while( ! $s[$p+=$d[$d]] ) {
    $s[$p]= ++$v;
    $d= ($d+1)%@d if $s[$p+$d[$d]];
}
printf $_<0?$/:" %".length($v)."d", $_ for @s[0..$v+$n-1];

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- tye        

In reply to Re: Spiraling integers by tye
in thread Spiraling integers by Elijah

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