There is J-4. It was a prototype/test of Mig-9 together with J-3, never went into production. So nobody knows until very recently like J-9, J-12, J-13 (all known date and design institute) and J-14 (nothing known).Chinese superstition is culturally ingrained CCP or not lol
Superstition is probably the purest of all human commonality along with inventing and passing on various creation theories since language was a thing.
I don't know whether numbering will conform but there are no J-4, J-14, J-24 etc but there is a DF-4. Although I suspect it was during a time before this Cantonese numbering superstition reached the mainland with such influence. All this 8 is lucky and 4 is unlucky etc came relatively recently if I recall correctly. But modern day CCP does seem to avoid 4 and prefer 8.
And we have DF-41.
There are skipped or unheard 4s, but there are equally lots of skipped and unheard "lucky" 8s or 9s. Such as J-19?, J18?
To everybody who still think CCP cares about the superstition shit, please be serious. (no offense intended). If CCP believes any of these craps it would not have survived to this day.