Thanks for the heads-up. That's pretty much what I assumed, but it's nice to have it confirmed. I must admit I find precedence a nightmare, and tend to avoid coding that depends on it.

map{$a=1-$_/10;map{$d=$a;$e=$b=$_/20-2;map{($d,$e)=(2*$d*$e+$a,$e**
2-$d**2+$b);$c=$d**2+$e**2>4?_:0}1..99;print$c}0..59;print$/}0..20;
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