And even faster again is a solution based on the property: 
  F(n) = floor((((1+sqrt(5))/2)**n) / sqrt(5)) + 0.5)

[download]
my $PHI = (1 + sqrt(5)) / 2;
sub fib ($) {int($PHI ** $_[0] / sqrt(5) + 0.5)}
say fib $_ for 0 .. 10;
__END__
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[download]

In reply to Re^2: Explain Fibonacci one-liner ?? by JavaFan
in thread Explain Fibonacci one-liner ?? by Anonymous Monk

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