From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f7be1,be6b7e036aa9236c X-Google-Attributes: gidf7be1,public X-Google-Thread: 11390f,be6b7e036aa9236c X-Google-Attributes: gid11390f,public X-Google-Thread: 103376,be6b7e036aa9236c X-Google-Attributes: gid103376,public X-Google-Thread: 101deb,be6b7e036aa9236c X-Google-Attributes: gid101deb,public X-Google-Thread: fa0ae,be6b7e036aa9236c X-Google-Attributes: gidfa0ae,public X-Google-Thread: 1094ba,be6b7e036aa9236c X-Google-Attributes: gid1094ba,public X-Google-Thread: 1164ba,be6b7e036aa9236c X-Google-Attributes: gid1164ba,public X-Google-Thread: 1014db,be6b7e036aa9236c X-Google-Attributes: gid1014db,public From: andrewg@microlise.co.uk (Andrew Gierth) Subject: Re: language wars (results 13 September) last posting Date: 1996/09/19 Message-ID: #1/1 X-Deja-AN: 181469738 distribution: inet x-geek: (V3.1) x-nntp-posting-host: microl.demon.co.uk references: <51bv60$8d@pheidippides.axion.bt.co.uk> cc: Norman H Cohen x-mayan-date: Long count = 12.19.3.9.1; tzolkin = 6 Imix; haab = 4 Chen organization: Microlise Engineering Ltd. gcs/it/cc d-(pu) s: +> a- C++++$ UACHV++++$ P--- L E++ W(--) N+++ o? K? w--- x-attribution: AG newsgroups: comp.lang.ada,comp.lang.apl,comp.lang.basic,comp.lang.c,comp.lang.fortran,comp.lang.perl.misc,comp.lang.pl1,comp.lang.rexx,comp.lang.pascal.misc,comp.lang.smalltalk Date: 1996-09-19T00:00:00+00:00 List-Id: >>>>> "Norman" == Norman H Cohen writes: > Andrew Gierth wrote: >> Useless (but true) factoid: >> >> The 13th day of the month is more often Friday than any other day >> of the week. Norman> I apologize for the off-topic posting (especially when it is Norman> cross-posted to so many newsgroups, and thus off so many Norman> topics at once), but it should be pointed out, before this Norman> becomes an urban legend, that this "factoid" is patently Norman> false! Oh dear. I don't have alt.folklore.urban on my server, or I might take this discussion there; in the absence of any obvious other place to direct followups to, we will have to stay off-topic for the time being. Email might be a good move... Norman> In any 2800-year cycle, the 13th will come out on each day of Norman> the week the same number of times. In fact, this is true of Norman> any 28-year cycle that does not include a century year that Norman> is not a leap year (e.g. 1800, 1900, 2100, 2200). You have missed, however, the fact that the calendar repeats every *400* years, not every 2800. 400 years is 146097 days, which is 20871 weeks precisely. However, 400 years is 4800 months, which is *not* divisible by 7. Therefore it is manifestly impossible for a specified day-of-the-month to fall equally on all days of the week. It so happens that the 13th falls most often on Friday. Skeptics are invited to write a program to do the calculation for themselves. -- Andrew Gierth (andrewg@microlise.co.uk) "Ceterum censeo Microsoftam delendam esse" - Alain Knaff in nanam