How do I create always 4 digit sequentially numbered and named file with shell script

I’m trying to create multiple *.txt files with 4-digit numerical names with leading zeros when needed. Script needs to stop when MAX varialbe is reached. This is using /bin/sh (not bash) but any help much appreciated. #!/bin/sh NUMBER=0001 MAX=0011 NUMBERFILE=$NUMBER”.txt” while [ $NUMBER -lt $MAX ]; do printf “\n$NUMBERFILE” # touch $NUMBERFILE NUMBER=$(( NUMBER+0001 ))…

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