2010/06/20 by Chamberlain Fong, Fong, Chamberlain
Computer Science · Mathematics · #Chaos-based Image/Signal Encryption #Computational Physics and Python Applications #Data Structures and Algorithms (cs.DS) #Discrete Mathematics (cs.DM) #FOS: Computer and information sciences #Probability and Statistical Research #cs.DM #cs.DS
paper · pdf · doi:10.48550/arxiv.1006.3913
added references to Lewis Carroll's early work on a perpetual calendar algorithm
openalex publication_date 2010/06/20 · arxiv created 2011/01/27 · arxiv updated 2011/01/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We propose a modification of a key component in the Doomsday Algorithm for calculating the day of the week of any calendar date. In particular, we propose to replace the calculation of the required term: \lfloor (x)/(12) \rfloor + x \bmod 12 + \lfloor (x \bmod 12)/(4) \rfloor with the term 2y + 10 (y \bmod 2) + z + \lfloor (2 (y \bmod 2) + z)/(4) \rfloor where x is an input 2-digit year; y is the tens digit of x; z is the ones digit of x; We argue the fact that our modification operates on individual base-10 digits makes the algorithm easier to calculate mentally.