Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!rutgers!psuvax1!vu-vlsi!swatsun!jackiw
From: jackiw@cs.swarthmore.edu (Nick Jackiw)
Newsgroups: comp.lang.pascal
Subject: Re: Day-of-week algorithm, please!
Message-ID: <2684@ilium.cs.swarthmore.edu>
Date: 13 Apr 89 18:01:55 GMT
References: <19065@adm.BRL.MIL>
Reply-To: jackiw@ilium.UUCP (Nick Jackiw)
Organization: Visual Geometry Project, Swarthmore College, PA
Lines: 20

I know this ain't too helpful, but...

There's a simple (five term) non-iterative formula called Ziegler's
Congruence (or possible Zegler's Congruence --- or was it Confluence? :-))
that returns 0..6 for the day of the week of any day since the last
MAJOR calendar adjustment (1818?).

I saw it six or seven years ago in a "Gem of the Month" block in _Creative
Computing_.

Not too helpful, eh?  But it was a LOT cleaner than any of the stuff
posted here so far.



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     _  _|\____    Nick Jackiw | Visual Geometry Project | Math Department
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