Assuming A-Z will suffice: 
my @original_array = qw(5 100 2 8 40);

my @letter_seq = do {
     my %letter_for;
     @letter_for{sort { $a <=> $b } @original_array} = ('A' .. 'Z');
     @letter_for{@original_array};
};

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Makeshifts last the longest.

In reply to Re: Render numeric sequence as array of letters by Aristotle
in thread Render numeric sequence as array of letters by gryphon

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