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The Whole Weeks Calendar is a leap week calendar designed such that each period within it contains a fixed number of 7-day weeks. The basic calendar is the Symmetry 4-5-4 Calendar, with months of 28-35-28 days in each common quarter.  But the leap week is placed according to McClenon's 5:40:400 leap week rules, with a leap week placed at the end of every fifth year, except for each 40th year not divisible by 400. While this is astronomically jittery, it forms a very systematic hierarchy of years, all of whole weeks at consistent, memorable intervals. The epoch of the calendar is Monday, January 1, 1 CE of the Gregorian Proleptic Calendar .

The months are given hybrid names, with Greek numerical prefixes combined with French Republican terminals:

Month number Month name (abrev) Weeks in month Days in month
Protose  (Pts)  28
Deuterose  (Dts)  35
Tritose  (Tts)  28
Tetrakal  (Tkl)  28   
Pentakal  (Pkl)  35
Hexakal  (Hkl)  28
Heptador  (Hpr)  28
Oktador  (Odr)  35
Ennador  (Edr)  28
10  Dekataire  (Dtr)  28
11  Hendekataire  (Hdr) 35
12  Dodekataire  (Ddr)  28
(in leap year) 5 35
The pentad is a five year cycle with 261 weeks, with a total of 1,827 days, unless it is the last Pentad in a common 40 year cycle.  In that case, it has 260 weeks, with 1,820 days.
The Tettarakontad is a 40 year cycle with 8 Pentads of 2087 weeks, with a total of 14,609 days, unless it is the last Tetarakontad in a 400 year cycle.  In that case, it has 2088 weeks, with 14,616 days.  
The tertrakosad is a 400 year cycle with 10 Tettarakontads, of 80 total Pentads, containing a total of 20,871 weeks (71 of which are leap weeks) of 146,097 days.

— Walter Ziobro