I'm looking for some unpublished notes called "Eta Lore," which are apparently related to a talk Douglas Hofstadter first gave at the Stanford Math Club in 1963. I know these notes exist because they're cited in the following articles:

- Hendel, R.J.; Monteferrante, S. "Hofstadter's Extraction Conjecture." The Fibonacci Quarterly 32(2), 1994.
- Chuan, W. "Extraction Property of the Golden Sequence." The Fibonacci Quarterly 33(2), 1995.
- Nillsen, R.; Tognetti, K.; Winley, G. "Bernoulli (Beta) and integer part sequences." A teaching module developed by the Australian Mathematical Society.

I've e-mailed the authors of the articles above, but I also thought I'd try asking around here, since none of the authors who've responded so far have been able to help. Any information on alternative references would also be appreciated.

**Motivation and Background**

I'm specifically interested in the definition of the function INT mentioned in Section I.33 of *Gödel, Escher, Bach*. The description there, in case it rings any bells, is: "The basic idea behind INT is that plus and minus signs are interchanged in a certain kind of continued fraction."

As far as I can tell, the notes I'm looking for are mostly about continued fractions and integer sequences---in particular, things called $\eta$-sequences and $\beta$-sequences (unfortunately, I have no idea what those are, and I haven't found any leads on OEIS).