A Stream script to generate pythagorian triples.
#!/usr/bin/perl

use Data::Dumper;
use Stream;

sub nplusone {

  my ($m,$n) = @{$_[0]}; 
  $n == $m+1 ? [1,$n+1] : [$m+1,$n];
}

sub ptrip {

  my ($m,$n) = @{$_[0]}; 
  
  [ ($n**2-$m**2), (2*$n*$m) , ($n**2+$m**2) ];
}

@triples =  sort { $a->[0] <=> $b->[0] || $a->[1] <=> $b->[1] } 
  map { [ sort {$a <=> $b} @$_ ] } 
  iterate(\&nplusone,[1,2])->transform(\&ptrip)->take(1000);

print Dumper(\@triples);

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In reply to Pythagorean Triples by marvell

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