Sorry, but that's wrong.

Your code will only work if @array1 is (1..7). If it is, say, ('H'..'N'), it will return the wrong result.

Sorry, but that's wrong. Your code will only work if @array1 is (1..7). If it is, say, ('H'..'N'), it will return the wrong result.
Two words: Problem Definition
Based on what you stated as your orginal problem then what I proposed will work. However, given your refinement of your problem set:

#
# Arguments: 
#    $a1 == reference to an array of scalars
#    $a2 == reference to an array of scalars
# Returns:
#    an array of scalars that are the result of 
#  prepending the contents of $a2 to the elements of $a1
#  or undef if the number of elements of $a1 and $a2 
#  are not the same.

sub prepender{
    my ($a1,$a2)=@_;
    my @ax=@$a1; # Dereference only for clarity.
    my @ay=@$a2; #    same as above

    return undef if $#ax != $#ay;

    return map { $ay[$_] . $ax[$_] } (0..$#ax);
}

#
# Sample call
my @array=('A'..'G');
my @array1=(10..($#array1+9));

my @array2=prepender(\@array,\@array1);
[download]

This includes some basic error checking....

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Peter L. Berghold -- Unix Professional Peter at Berghold dot Net
	Dog trainer, dog agility exhibitor, brewer of fine Belgian style ales. Happiness is a warm, tired, contented dog curled up at your side and a good Belgian ale in your chalice.