This webpage belongs to www.alexandriancomputus.net, which is a website promoting [Jan Zuidhoek (2019) Reconstructing Metonic 19-year Lunar Cycles (on the basis of NASA’s Six Millennium Catalog of Phases of the Moon): Zwolle], and shows the table containing the five Alexandrian Metonic 19‑year lunar cycles being part of this pioneering book, which is available via this website.

Five Alexandrian Metonic 19-year Lunar Cycles
AD	Anatolius’	archetyp. Alex.	Festal Index	Theophilus’	classic. Alex.
304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322	8 April 28 March 16 April 5 April 24 March 12 April 1 April 20 April 9 April 29 March 17 April 6 April 26 March 14 April 3 April 23 March 11 April 31 March 19 April	6 April 26 March 13 April 2 April 22 March 10 April 30 March 18 April 7 April 27 March 15 April 4 April 24 March 12 April 1 April 21 March 9 April 29 March 17 April	6 April 26 March 14 April 2 April 22 March 10 April 30 March 18 April 7 April 27 March 15 April 4 April 24 March 12 April 1 April 21 March 9 April 29 March 17 April	6 April 25 March 13 April 2 April 22 March 10 April 30 March 18 April 7 April 27 March 15 April 4 April 24 March 12 April 1 April 21 March 9 April 29 March 17 April	5 April 25 March 13 April 2 April 22 March 10 april 30 March 18 April 7 April 27 March 15 April 4 April 24 March 12 April 1 April 21 March 9 April 29 March 17 April
Table 8: Comparing the two lost supposed to be ante‑Nicene and the three well‑known post‑Nicene Alexandrian Metonic 19‑year lunar cycles to each other

Anatolius’ 19-year lunar cycle is the lost very first Metonic 19‑year lunar cycle, invented by the great Alexandrian computist Anatolius before he became bishop of Laodicea in AD 268; the archetypal Alexandrian 19-year lunar cycle, also simply referred to as the archetypal Alexandrian cycle, is the lost common archetype of the three well-known post‑Nicene Alexandrian Metonic 19‑year lunar cycles. Both of these Metonic 19‑year lunar cycles were constructed (in all probability before AD 325) and reconstructed (recently) according to four computistical principles: the principle concerning the spring equinox, the principle concerning the crescent moon, the principle of periodicity, and the principle of metonicity.

The classical Alexandrian 19-year lunar cycle, also simply referred to as the classical Alexandrian cycle, is Annianus’ 19-year lunar cycle, being the Metonic 19‑year lunar cycle opted for by the Alexandrian monk and great computist Annianus (around AD 412). The classical Alexandrian cycle forms the Metonic basic structure both of Dionysius Exiguus’ Paschal table (AD 525) and of the Easter table of Beda Venerabilis (AD 725).

We observe that there exists a 2‑day gap between on the one hand Anatolius’ 19-year lunar cycle and on the other hand the other four Alexandrian Metonic 19-year lunar cycles; this gap dates in all probability from before the first council of Nicaea (AD 325), and is therefore referred to as the ante-Nicene 2‑day gap.

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Five Alexandrian Metonic 19-year Lunar Cycles