
My Knuth reward check - chrismealy
http://www.arcfn.com/2011/05/my-knuth-reward-check.html
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kens
Wow, I was not expecting this article of mine to appear on Hacker News. The
error I found was in volume 4a page 574 (as the memo line on the check shows).
The solution to exercise 67 on that page says a particular circuit uses 6 ANDN
gates, which I thought should be NAND gates. It gets a bit more complicated
because Knuth was referring to the ANDN op code for MMIX, but there was still
a mistake. (The other error I noticed was n choose k on page 824, but I
checked the errata and it had already been found.)

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VMG
well, what was the mistake then?

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philh
To save anyone else the trouble: the errata can be found at <http://www-cs-
faculty.stanford.edu/~uno/taocp.html> , but it hasn't been updated to include
this.

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Evgeny
_I have to admit that trying to find an error in a book is a strange vacation
goal_

Come on, I can only wish I was smart enough to set myself such a goal
realistically. And to reach it? Would make this a vacation of a lifetime.

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closure
Found two errors back around 2000 or 2001. Cashed both checks. Figure he would
want to keep the balance correct on his accounts. :) Only slightly regret it.

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erikpukinskis
So it's a fake check?

~~~
JoachimSchipper
Knuth stopped writing real checks due to the possibility of check fraud:
<http://www-cs-faculty.stanford.edu/~knuth/news08.html>.

For that matter, almost all recipients considered the bragging values of the
checks to be worth more than the few dollars in reward money; very few (or
none) have been cashed.

~~~
hugh3
Still seems like a bit of a gyp. I hope that Knuth is willing to provide a
real cheque for real money if you ask. He did, after all, promise real money.

~~~
alexandros
I'm sure you can sell that for more than $2.56. Hell, if you get one I'll
commit to buy it off you for $5 plus postage. Email in profile.

~~~
joe_bleau
Why would you want a DK check with someone else's name on it?

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mattdeboard
I assume the error wasn't included to save Mr. Knuth from an avalanche of
people "finding" the same error and demanding a check.

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michael_dorfman
That's not the way it works; the "finder's fee" goes only to the first person
to find an error.

Knuth also pays for suggested improvements, but these are a bit harder to get.

(Not that you asked, but I've got one of each.)

~~~
mattdeboard
Cool. Thanks for the clarification.

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iwwr
This will get downvoted but...

Until we actually know what the error was, _it's not true_.

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JoachimSchipper
What are you trying to say? That the author may be lying? He would be found
out soon enough - it would be stupid to try. That the error is not real? Knuth
seems to think so, and the author is primarily claiming to have received a
check anyway.

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iwwr
It would be reasonable to reveal the error in question, rather than tease us
with just the cheque. Besides, Knuth or not, it's still valid when we learn
what it is.

~~~
JoachimSchipper
In case you hadn't noticed: <http://news.ycombinator.com/item?id=2525309>.

~~~
iwwr
Well then, -10 karma, it was worth it :)

