User blog comment:QuasarBooster/Bashicu matrix version 4 in Python!/@comment-35470197-20191109233117/@comment-35470197-20191110060755

Never mind. BMS is sufficiently difficult. Although you might know, the article on primitive sequence system, i.e. BMS restricted to 1-rowed matrices, might be helpful to understand the parent relation, because it includes a Python code. (I am not checking the correctness of the code, though.)