Shell Script To Print Pyramid - Using while Loop

 #!/bin/bash
 # Usage: scriptname argument
 # Here argument is height of pyramid
 # Output would be pyramid pattern of stars
 #       0                 *
 #       1                ***
 #       2               *****
 #       3              *******
 #       4             *********
 #       5            ***********
 #       6           *************
 #       .          ***************
 #       .         *****************
 #       .        *******************
 #       n-1     *********************
 #                ---\/--- | ---\/---
 #                  n - 1      n - 1
 #
clear
n=$1
row=1;
echo -e "\033[47m"
        while [[ $row -le $n ]]
        do
        loop=1;
        spaces=$((n-row))
        stars=$((2*row - 1))

           while [[ $loop -le $spaces ]]
           do
                echo -n ' '
                let loop++
           done
        loop=1;
           while [[ $loop -le $stars ]]
           do
                echo -e '\033[43m*\033[47m\c'
                let loop++
           done
        loop=1;
           while [[ $loop -le $spaces ]]
           do
                echo -n ' '
                let loop++
           done
        echo
        let row++
        done
echo -e "\033[0m"
unset row loop spaces stars n

Output:
[root@localhost blog]# sh while_pyramid 22