>>19284732>>19284732The dex number corresponding is just a coincidence though.
The order that the pokedex is in for Gen 1 is the order that the pokemon were created, so Rhydon first, etc. So, keep in mind if you look at the pokedex we know, with Bulbasaur first, the Rhydon first dex looks completely random. Basically, Rhydon first dex you have scattered evolutionary lines and Bulbasaur first dex everything is in order.
When they took out a whole bunch of those pokemon because reasons, there were blank spots left, which are the missing number pokemon.
When you glitch pokemon and trade between RBY and GS, those missing numbers for the GS dex are in order of the GS dex. Instead of the order in which pokemon were created, you see pokemon filling the empty missing number gaps in the official dex order.