I am learning shell bash now, and tried to figure it out how to compare expr result on IF condition.
Basically want to return only odd natural numbers

The code

a=1

while [ $a -lt 10 ]
do
    echo "test " $a % 2 " = " `expr $a % 2`
    if [`expr $a % 2`] 
    then
        echo $a
    fi
   
    a=`expr $a + 1`
done

I wish the result should be
1
3
5
7
9