If there is a connection, I would expect it to be related to the fact that the $j$ invariant is connected to both Moonshine and to class field theory. Note that 7, 11, 19, 43, 67, and 163 are all the absolute values of odd discriminants with class number 1. (Strangely, 3 is missing from the list! Otherwise the list is complete.)
Stopple
- 11.1k
- 3
- 43
- 65