Ancient Greek Numbers
What do you think this is?
Courtesy of Beinecke Rare Book and Manuscript Library, Yale University
Yes, this is a multiplicaton table dating from ca.100 AD. The ancient Greek numbering system was based on their alphabet of 24 letters plus three other symbols borrowed from the alphabets of trading partners. The numbers 1 through 10 are written across the top and down the left column in the same pattern we often see today. They continued using additional letters for multiples of 10 and 100. See if you can find these examples in the table.
The multiplication table you are viewing had to be memorized. Thus, we call this a "ciphered" numbering system.
(Reproduced from a handwritten copy of Introductio arithmetica attributed to Nicomachus of Gersa. This particular copy is dated 1538 but the original was ca. 100 AD.)