1.) Key the first 3 digits of your phone number into a
calculator (do not key in your area code).
2.) Multiply by 80.
3.) Add 1.
4.) Multiply by 250.
5.) Plus last 4 digits of your phone number.
6.) Plus last 4 digits of your phone number again.
7.) Minus 250.
8.) Divide by 2.
9.)...