User blog:Kenstallyies30/Check Modulus 24 in the field, post 1

Modulus 24 is one of the modular arithmetics used in some checksum algorithms. One example is found at Witch Reference Number (WRN), one of the identification systems for witches: Legend: The checksum letter is calculated as follows: Allocate weightings to 10 digits according to the following table: Multiply each numeric character by its weight, and add it to a sum.
 * N: 0–9
 * A: A–Z
 * *: Unique
 * #: Always W, for 'witch'
 * @: Checksum letter

Divide the number by 24 using modular arithmetic or long division.

The checksum character is obtained by converting the remainder to a letter according to the table below: Examples (0000000001WJ to 0000000040WS): Examples (some witches):
 * 0000000001WJ
 * 0000000002WQ
 * 0000000003WD
 * 0000000004WL
 * 0000000005WT
 * 0000000006WG
 * 0000000007WN
 * 0000000008WA
 * 0000000009WJ
 * 0000000010WK
 * 0000000011WS
 * 0000000012WF
 * 0000000013WZ
 * 0000000014WW
 * 0000000015WH
 * 0000000016WP
 * 0000000017WC
 * 0000000018WK
 * 0000000019WS
 * 0000000020WV
 * 0000000021WI
 * 0000000022WY
 * 0000000023WB
 * 0000000024WX
 * 0000000025WR
 * 0000000026WE
 * 0000000027WM
 * 0000000028WV
 * 0000000029WI
 * 0000000030WJ
 * 0000000031WQ
 * 0000000032WD
 * 0000000033WL
 * 0000000034WT
 * 0000000035WG
 * 0000000036WN
 * 0000000037WA
 * 0000000038WJ
 * 0000000039WQ
 * 0000000040WS
 * Wicked Witch of the West - 9141599705WP
 * Stella the Bubble Witch - 7096335370WD
 * Lucinda the Witch - 1010447484WM
 * Pheobe Ravenson - 9545225595WZ