I think this snippet explains your predicament.

>perl -e "$a=[120]; for (-1..@{$a}){print qq($_\n)};
   print qq(  \$a=$a    \@a=@{$a}  value=$a->[0]);"

OUTPUT:
-1
0
1
  $a=ARRAY(0x224f44)    @a=120  value=120
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Note that $a is an array ref, and @a in a print context returns the equivalent of join (' ',@a), which is a single element of 120.

To get your "for" right, you need to use

  for(-5..$term->[0])
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