1920 cent missing 1 obverse

[Junkdrawer]

A discovery while searching a lot of 600+ wheat pennies. I found a penny, obviously from 1920, but clearly missing the #1 from the date. Under 20x magnification it did not appear to be scratched offi. Is this a known error?

[RWB]

I have a similar cent but it's missing the "3" -- or is it a "2" or a "4"...?

 

Filled die.

[cpm9ball]

Grease-filled dies are pretty common on Lincoln cents.

 

Chris