It is my understanding that the AGC is the computer within the PGNCS. Terminology varies, as the last link below from NASA notes.

So far as I can tell, the AGC maintained the state vectors for the KF. Ground control would run batch mode least squares solutions, and pass it on to the LM, where the updates to the state vector would be applied by hand. I freely admit to not having worked through the code, but I believe the state vector update computations occur here: http://www.ibiblio.org/apollo/listings/Comanche055/MEASUREME...

sources: http://www.ieeecss.org/CSM/library/2010/june10/11-Historical...

http://en.wikipedia.org/wiki/Apollo_Guidance_Computer

http://en.wikipedia.org/wiki/Apollo_PGNCS http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/2009001...

Thanks, that helps. I've always wondered what the variables of the state vector were -- position, velocity, etc. it appears from the link that it could be a 6x6 of those two (position, velocity in x, y, and z), or a 9x9 when including radar/landmark bias. Now I know!