Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site cbneb.UUCP
Path: utzoo!watmath!clyde!cbosgd!cbsck!cbneb!adm
From: adm@cbneb.UUCP
Newsgroups: net.games.trivia
Subject: Re: Dumb trivia because I am bored.
Message-ID: <2940@cbneb.UUCP>
Date: Thu, 7-Feb-85 09:22:09 EST
Article-I.D.: cbneb.2940
Posted: Thu Feb  7 09:22:09 1985
Date-Received: Fri, 8-Feb-85 03:21:57 EST
Sender: adm@cbneb.UUCP
Organization: AT&T Bell Laboratories, Columbus, OHIO
Lines: 27
Nf-ID: #R:gondor:-159400:cbnap:14000001:000:1030
Nf-From: cbnap!tjl    Feb  7 08:50:00 1985

/* BLANK line  or  Blankity-blank line if you prefer */


>      2)  How many calanders do you need to have a 'perpetual' calander?
>	  (Ie: For all eternity you would need no more than X calanders
>	  to represent whatever year you may be in.)

The proposed answer of fourteen calanders[sic] works for recent centuries
and the foreseeable future; that is a 1/1/** for each day of the week plus
another seven for leap years.

However, others are needed for a perpetual calendar.  For example, a
special one is needed for 1752.  September of that year is missing 
eleven days.  Try cal 9 1752 on your UNIX(c) system.  That should
add over a thousand contiguous years to the perpetual calendar.

If I remember my ancient history correctly, the caesars Augustus and
Julius both 'stole' a day from February to make their months longer.
I'm sure that would add several calendars for both the transition
years and however they looked before that. (Aren't leap years a 
fairly new invention?)

Answer: 15 + whatever the romans needed.