The Prime Wavelet Tree: Compressing the Carmichael Numbers
Abstract
We present two number-theoretic compression techniques. The first is \textit{local}, and compresses individual numbers. The second is \textit{global}, and compresses the entire set of numbers using a \textit{prime wavelet tree}, which is a data structure of independent interest. Our techniques apply to any set of numbers satisfying a Korselt-like criterion. We demonstrate our compression techniques using the recently completed tabulation of all 308,279,939 Carmichael numbers less than 1024 that occupies $18.4$ gigabytes as text. When combined with standard compression techniques and a heuristic choice of divisors, the resulting file is $588.7$ megabytes ($31.2$ times smaller than the text file). The initial $80$-bit numbers now use about $15.3$ bits.
Related
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- Compressing multivariate functions with tree tensor networks
- A Note on Carmichael Numbers of the form $ N=(d+1)(3d+1)(4d+1)$
- A Korselt Characterization of Carmichael Numbers of the Form (aCn+1)(aCn+1+1)(aCn+2+1)
- Idempotence in Carmichael and Giuga numbers and its application to the Agoh-Giuga conjecture
BibTeX
@misc{gupta2026prime,
title = {{The Prime Wavelet Tree: Compressing the Carmichael Numbers}},
author = {Ankur Gupta and Jonathan Webster and Sylvia Webster},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.02550},
eprint = {2610.02550},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.02550},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - The Prime Wavelet Tree: Compressing the Carmichael Numbers
AU - Ankur Gupta
AU - Jonathan Webster
AU - Sylvia Webster
PY - 2026
DA - 2026/10/01
PB - arXiv
DO - 10.48550/arxiv.2610.02550
UR - https://arxiv.org/abs/2610.02550
AB - We present two number-theoretic compression techniques. The first is \textit{local}, and compresses individual numbers. The second is \textit{global}, and compresses the entire set of numbers using a \textit{prime wavelet tree}, which is a data structure of independent interest. Our techniques apply to any set of numbers satisfying a Korselt-like criterion. We demonstrate our compression techniques using the recently completed tabulation of all 308,279,939 Carmichael numbers less than 10^24 that occupies $18.4$ gigabytes as text. When combined with standard compression techniques and a heuristic choice of divisors, the resulting file is $588.7$ megabytes ($31.2$ times smaller than the text file). The initial $80$-bit numbers now use about $15.3$ bits.
ER -