Casa Moctezuma
What it is
The count of a living tradition, offset 134 days from Caso, with the day starting at solar noon and the year opening on 18 March.
Why it does not fit the others' formula
There is a discrepancy inside its own materials: its printed calendar says 17 March and its class says 18. The 18th is followed here because two of its sources support it against one.
The algorithm
The full algorithm for this count lives as a file of its own, kept outside the code and sealed, so that it outlives the app and so that whoever inherits it knows what to implement.
What is published here is its data sheet — the anchor, the offset, when the day starts and when the year opens — and its control dates, which is what lets anyone check whether a calculation is right.
How to cite this page
Alma Mexica, «Casa Moctezuma», The five counts. Last revised 2026-09-17. https://almamexica.org/en/counts/casa-moctezuma/