6-superstitious_numbers

#!/usr/bin/env bash
# A Bash script that displays numbers from 1 to 20 and:
# displays 4 and then bad luck from China for the 4th loop iteration,
# displays 9 and then bad luck from Japan for the 9th loop iteration,
# displays 17 and then bad luck from Italy for the 17th loop iteration.

i=1;

while ((i < 21))
do
    echo "$i"
    case "$i" in 4)
		     echo "bad luck from China";;
		  9)
		      echo "bad luck from Japan";;
		  17)
		      echo "bad luck from Italy";;
    esac
    ((i++))
done