Preferably in Bash

Next, write a script that runs the above code for the values from 20000 to 40000 in increments of 1000 . For each value, execute the code 20 times and take the average. The output of the script should be the arrays dimension followed by the time taken for the computation, one pair per row. For example: 200001.14961 210001.23928 . 400004.4562