I was very impressed by the construction of diagonal numbers (of Georg Cantor) as described in one of the books I am reading: Alan Turing: The Enigma by Andrew Hodges. Decimal representations of fractions were printed in a list, one below the next, with their decimal places aligned. The diagonal number’s digit are made up of the first digit of the first list entry followed by the second digit of the second entry, the third digit of the third entry and so on. This fascinated me. I have just an inkling of the mathematical consequences of the diagonal numbers that result from the tables of fractions (and the series of fractions used for to create the table). I want to learn more about this. Below is my representation of a diagonal number table.