create a string starting with 1 and concat n+1, until you reach the charcter length you want, in this case 32

charruler.sh

#!/bin/sh
# reset num to zero unset iteration if you want to run it over again.
num=0; unset iteration; while [[ $num -lt 32 ]] # continue to increase iteration until $num is 32
do
  let num=$((1+$num))             # increase num by 1
  let modu=$((num%10))            # get digits between 0 and 9
  iteration="${iteration}${modu}" # concat previous iteration with modu
  printf "%s\n" "${iteration}"    # print iteration as a string so you can go past 20 decimal limit, 
done                              # you can use echo instead of printf if you want