Remember those IQ tests (or whatever name they are camouflaged under

nowadays) in which you are asked to prode the next member of a sequence of

numbers? (What is the next number in this sequence: 1, 11, 21, 1211,

111221, 312211,…?)

Well, back in the early 1970s, Neil Sloane published a Handbook of Integer Sequences, intended as a start on listing ALL possible integer sequences of

any interest at all. This project gre and grew — I have a 1995 book titled

The Encyclopedia of Integer Sequences, which was another milestone.

This is now all on the internet, of course, and you can look up your

favorite sequence here. If you

liked Prime Obsession, check out these: A100060, A102522, A102523,

A102524. (Click the “Sequence Number” radio button & put the sequence

number in the text box.)

(Thanks to Gary Adamson for noticing these entries.)