Just when you thought you've seen all the utterly pointless number sequences that bored, sexually frustrated mathematicians could dare dream up, one'll always pop up and surprise you, not unlike an anti-personnel mine. Today's pattern : Aronson's Sequence!

Good old Aronson (no relation to Daniel-son) built this number sequence off of the fact that the ordinal numbers in English will always end in 'th'. So, he started with the following setence :

T is the first letter in this sentence.
And the number sequence starts at 1. But then, T is also the fourth letter, so...
T is the first and fourth letter in this sentence.
And the number sequence is 1,4. The next T is at 11.
T is the first, fourth, and eleventh letter in this sentence.
1, 4, 11. Then it's followed by 16, 24, 29, 33, 35, 39, 45, 47, 51, 56, and so on, and so forth, with endless Ts cropping up and demanding your attention.

Before you say anything else, yes, Virginia, this sequence is totally useless, but somehow this Aronson chap used it to get his name first in mathematical literature, where he'll be puzzled over and cursed at for posterity, and now he's in your brain, where you'll never forget him (or forgive him, for that matter).