To prefix zero in front of digits
In bash, prefixing zero needs more of formatting, than direct way. This example shows how to prefix zero at the same time maintain the digit width.
#!/bin/bash
export TXT=Number
for LP in `seq -f "$TXT%02g" 12`
do
echo $LP
done
The output will have the same width.
Number01
Number02
Number03
Number04
Number05
Number06
Number07
Number08
Number09
Number10
Number11
Number12