On Tue, Jan 26, 2016 at 02:36:28PM -0500, Doug McIlroy wrote:
> That is exactly right. Unix was up and running as a time-sharing
> system with remote access before a primitive DOS emerged from DEC.
> The chess problem was enumeration of closed knight tours.

"The processor arrived at the end of the summer [1970], but the PDP-11
was so new a product that no disk was available until December. In the
meantime, a rudimentary, core-only version of Unix was written using
a cross-assembler on the PDP-7. Most of the time, the machine sat in
a corner, enumerating all the closed Knight's tours on a 6×8 chess
board—a three-month job."
	-- https://www.bell-labs.com/usr/dmr/www/hist.html

Cheers, Warren