Row: 769801AB3254 (Webern Quartet op. 28).

There are 479001600 rows and 10395 distinct mapped opposites in base 12.
There are 46080 rows for each mapped opposite in base 12.

The distinct degrees of mapped opposites in base 12 are: 12,10,8,6,4,2.
The corresponding cardinalities of mapped opposites by degree are: 4160,2304,1440,1440,970,81.

The mapped opposite of 769801AB3254 is 62478B591A30 and its degree is 4.
The number of rows in this subset is 970 * 46080 = 44697600.
Sharing the same mapped opposite, each one of the 12 transpositions of 769801AB3254 pertains to the same subset.
The number of rows in this subset without transpositions is 970 * 46080/12 = 3724800.