someString | sed 's/.//1' this line works and delete the first character
someString | sed 's/.//$j' but when I try to loop and use the index no, it does not work.
upperKeyword="secret"
for (( i=0; i<$index; i++ ))
do
    for (( j=i+1; j<$index; j++ ))
    do
        x=${upperKeyword:$i:1}
        y=${upperKeyword:$j:1}
        if [ "$x" == "$y" ]
        then
            upperKeyword=`echo $upperKeyword | sed 's/.//$j'`
            break
        fi
    done
done
echo $upperKeyword
Please help
