Letter to number tables, Pythagorean and Chaldean

What the columns mean

id (string)

Stable row identifier, unchanged across versions

chu (string)

Letter, uppercase

pythagoras (int)

Value in the Pythagorean system, 1 to 9

chaldean (int)

Value in the Chaldean system, 1 to 8; that system uses no 9

nguyen_am (string)

co when this character is a vowel, used to calculate the Soul number

nguon (string)

Kind of source for this row, one or more parts separated by semicolons, each being tinh-toan (computed by the engine), quy-uoc-truyen-thong, quy-uoc-he-hien-dai (convention of a tradition or of a modern system), van-ban (with the work after a colon) or bien-tap (with details); static details are also in the metadata nguon_chi_tiet, and the two largest datasets give them only there; which column belongs to which part is given by each column's loai_bang_chung in the metadata

ghi_chu (string)

Where the schools disagree on this row; empty when they do not

Release

Data release ID

2026.10.27-cd6fca71 · manifest.json

Dataset version

1.1.2

Dataset last changed

2026-10-27

Generated

2026-10-27 08:07 UTC

Rows

33 rows, 7 columns

Schema hash

45d7af1239604b39…Copysha256 of each column's name and type

Download this exact release

• chu-sang-so-than-so-hoc.csv · 3.7 KB · sha256 a2687e63b178b930…Copy
• chu-sang-so-than-so-hoc.json · 7.8 KB · sha256 8ef2c9e111405989…Copy
• chu-sang-so-than-so-hoc.meta.json · 19.6 KB · sha256 4663ebdf34269afc…Copy

The “CSV for Excel” button at the top serves a copy with a BOM, so its hash differs from the CSV here.

Changes

Version 1.1.2 (2026-10-27), type documentation: The general note drops "ancient values" for the Chaldean table: it is the table Cheiro printed in 1926 under that name, and its ancient origin is a tradition with no documentary evidence. The data is unchanged byte for byte.

Changelog of every dataset (CHANGELOG on GitHub)

Method

This dataset goes through no calendar model.

Engine version of the release: 2.0.0.

Verification

Evidence types in this dataset, and how far each can be checked:

• C. Convention of a tradition or of a modern system: correct by that convention, neither true nor false in an empirical sense; where schools differ is recorded in the diem-bat-dong-giua-cac-phai dataset.

Provenance

A lookup table copied from the source texts or systems named in nguon_thu_tich and the nguon column.

• C. Convention of a tradition or of a modern system: chu, pythagoras, chaldean, nguyen_am

Cite this dataset

Nhật Nguyệt (2026). Letter to number tables, Pythagorean and Chaldean (version 1.1.2, data release 2026.10.27-cd6fca71) [Data set]. CC BY 4.0. DOI 10.5281/zenodo.23009396. https://nhatnguyet.org/en/bang/chu-sang-so-than-so-hocCopy

The concept DOI always resolves to the latest release. Zenodo mints a DOI for each release after it is published, and the next release records it in the manifest.

Licence and limitations

Released under CC BY 4.0: reuse commercially, adapt freely, attribution is all that is asked.

Source: Nhật Nguyệt (nhatnguyet.org), CC BY 4.0

This dataset records cultural and calendrical conventions, not scientific claims. It is suitable for cultural research, NLP, and calendar applications. It is not intended for predicting events, evaluating people, or making decisions that affect anyone.

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