It works for 9 on a 64 bit system, which is why I didn't notice it's broken, but it is indeed broken on 64 bit systems.

You could try to fix it with something like this, but as is that's too long and I don't feel much like golfing it now.

perl -e 'printf"%*.0f\n",$t+abs,(1x abs)**2for 1..($t=pop),1-$t..-1' 9
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