2010/10/05 by Chamberlain Fong, Fong, Chamberlain, Mike Walters +2
Computer Science · Physics and Astronomy · #Data Structures and Algorithms (cs.DS) #Discrete Mathematics (cs.DM) #Distributed and Parallel Computing Systems #Distributed systems and fault tolerance #FOS: Computer and information sciences #Space Science and Extraterrestrial Life #cs.DM #cs.DS
paper · pdf · doi:10.48550/arxiv.1010.0765
7th International Congress of Industrial and Applied Mathematics (2011)
openalex publication_date 2010/10/05 · arxiv created 2011/08/08 · arxiv updated 2011/08/09 · 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 -[ (x+11(x \bmod 2))/(2) + 11 ((x+11(x \bmod 2))/(2)\bmod 2)] \bmod 7 for a 2-digit input year x; Although our expression looks daunting and complicated, we will explain why it is actually easy to calculate mentally.