Buddhist endless knot, but of books

[silky]

related googling leads me to have to also discuss the eight auspicious symbols

https://en.wikipedia.org/wiki/Ashtamangala

[Porges]

like … structurally? publish X books that intertwine and none of them is indicated as ‘the first’

sounds like a Georges Perec idea

[silky]

no, that's not what i had in mind; but that's far better :D