My first thought was that these might be what are called śṛṅkhalās, chains, which I've encountered in MSS of the Aṣṭādhyāyī. These are aids to memory and recitation, like this:

raṣābhyāmubhauṣṭunodaḥsthāṣṭau

At first they look completely nonsensical.  The key is that they consist of a concatenation of the opening part of the first and then each twentieth sūtra in each pāda.  The final word aṣṭau signifies that there are eight sūtras to the end of the pāda. In the above, raṣābhyām..., it's sūtras 8.4.1, 8.4.21, 8.4.41, 8.4.61, and then 8 sūtras to the end (counting 8.4.61).

You might be looking at something like this, but I can't make it work (in a few minutes) for your case.