This is so embarrassing...

As Piotr Piatek has patiently explained to me in private e-mail, the
Gray-code algorithm I gave is equivalent to the one Warren Davis
showed... I misread Warren's description and didn't realize that his
"b(i)" notation referred to individual bits in n-bit words; instead,
I thought each b(i) represented an entire n-bit word.

My apologies, Warren.

-Andy

Andrew Warren - fastfwd@ix.netcom.com
Fast Forward Engineering, Vista, California
http://www.geocities.com/SiliconValley/2499