In uk.sci.astronomy message ,
Sun, 24 Feb 2008 09:52:19, Mike Dworetsky .
com posted:
The Roman Indiction period of 15 years was for taxation calculations,
and was introduced by Constantine the Great in 312AD. Or so it says in
the Calendar FAQ.
It is also used in the construction of the Julian Day Number.
No. It is used, but it is not also used; it plays no part in the
calculation of Julian or Gregorian Easter. It is one of the three
cycles which jointly were, extrapolating back, at zero in B.C. 4713;
JDN 0.0 is proleptic Julian BC 4713-01-01 noon GMT.
The FAQ by Claus TĒnderings has an extensive section on calculating the
date of Easter.
http://www.tondering.dk/claus/cal/calendar28.html
But the FAQ shows no evidence of traceability to the Calendar Act,
Clavius, or legal authority elsewhere (though the algorithms are
correct).
--
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Web URL:http://www.merlyn.demon.co.uk/ - FAQqish topics, acronyms & links;
Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc.
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