thank you! and chainmail lists armor classes from 1 to 8 rather than from 9 to 2 (or from 10 to 17, which is extremely modern). descending armor class as it appears in D&D is a post-chainmail modification by gygax, seemingly because a system similar to target-20 may have been used in the game at some time prior to publication.
i thought it’d be more interesting to have the original values to encourage people to look at it as a distinct set of rules.