OFFSET
0,1
COMMENTS
The months are Nisan, Iyyar, Sivan, Tammuz, Av, Elul, Tishri, Heshvan, Kislev, Teveth, Shevat, Adar. A leap month of 30 days, added between Shevat and Adar, is called Adar I, where the final month is then called Adar II. Heshvan and Kislev (the 8th and 9th months) may each have 29 or 30 days, depending on the calendrical rules.
36.22% of all years are "regular"; 25.51% are "deficient", with 29 days in both Heshvan and Kislev; 38.27% are "complete", with 30 days in both months. Note that Hebrew year 5760 is a 13-month leap year. - Robert B Fowler, Mar 08 2022
See A350458 for other comments, references, links, formulas, programs.
REFERENCES
N. Dershowitz and E. M. Reingold, Calendrical Calculations, Cambridge University Press, 1997.
LINKS
Wikipedia, Hebrew calendar Four gates, Types of Hebrew calendar years and their frequencies.
EXAMPLE
A regular year has the pattern 30, 29, 30, 29, 30, 29, 30, 29, 30, 29, 30, 29.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved