Decode txt file n number of times

Decode_n_times

#!/bin/bash

# n can not be greater than 25!
# if you need more than 25 then i would suggest a loop that manipulates a global variable $temp!
decodeFile($n, $file) {
if (n == 0) echo $file
else {
  base64 -d $file > $file 
  echo $(decodeFile($n-1, $file)
  }
}

unset initStr
initStr=`cat ./pw_encoded_oneline.txt`
unset $file
$file = `echo $initStr | base64 -w0 -d`
$results = decodeFile(13, $file)
echo $results