Last week, I wrote about one of my more spectacular failures, which involved a progression that began 1, 2, 4, 8, 16, 32, but then rather than continuing sensibly as 64, 128, ..., instead exploded into 273, 65569, 4294967361, and 1.5x10^{82}. The next term is a little over 2^{65569} and the term after that a little over 2^{4294967361}, which has about a *billion* digits when written out in full.

Joshua Zucker suggested that I submit this to the On-Line Encyclopedia of Integer Sequences, which I did. So I've now been immortalized in Sequence A137181. I can see my tombstone now: “He failed...BIG.”

Several years ago I was giving a guest lecture in a colleague's Algorithms class, when I encountered immortality of a different sort. The students were asking me about how I invented “Okasaki trees”, and were dumbfounded when I didn't know what they were talking about. How could I not know about Okasaki trees when I invented them? “Well,” I told them, “I've invented a lot of different data structures, and most of them are trees of one kind or another. But I've never called any of them Okasaki trees.” After a bit more digging, it turned out that my colleague (who wasn't there that day) had been telling them the previous week about my simplification of red-black trees, and *he* called them Okasaki trees.

The lasting result of this is that I now have a friend at work who ribs me about Okasaki trees every chance she gets.

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