On Wed, 23 Sep 2020, Clem Cole wrote:

> Dave: Seymour used ones complement on the 3000 and 6000 series.
> Maybe there?   The primary HLLs I used on the CDC boxes were FTN and Pascal,
> but I would not be surprised if that was were you saw it.

Could be CDC, yeah, but this was a few decades ago...

-- Dave