The lineage of Abū al-Yaman al-Kindī is cited as an extended case in which the names Zayd and al-Ḥasan recur through alternating generations.
The example shows that a long genealogy may contain intentional repeated personal names. Repetition alone does not establish omission, transposition, or accidental duplication.
Research method: break the genealogy into successive father–son links, attach each name to its corresponding ibn, and then compare generations, related family biographies, and independent records.