Identify old Fairchild component

A

AnalogKid

Guest
#1
Going through old home inventory, came across this part:
Fairchild (logo)
p/n 931159
Date code 7123
24-pin ceramic hermetic DIP
No other markings top or bottom

Any digital geezers out there recognize this? My guess is a (possibly custom-programmed) bipolar PROM, but the part number doesn't match their pattern.

Thanks

ak