I am not Jewish. I self-identify as Christian. I was exploring this calendar for my own edification, and to gain historical and cultural perspective.
I understand the odd numbered months to be 30 days in length, i.e. Nisan (01), Sivan (03), Av (05), Tishrei (07), Kislev (09), Sh'vat (11), and in leap years Adar I (13).
Conversely, the even numbered months are 29 days long, i.e. Iyyar (02), Tamuz (04), Elul (06), Cheshvan (08), Tevet (10), and Adar [ II } (12).
For the current year, 5779, I was counting the number of days from Rosh Chodesh to Rosh Chodesh for the entire year, and it seems your algorithm inverts the lengths of months, odd numbered months being 29 days, even months 30 days, excepting Adar I which seems to me to be 30 days.
Can someone help unconfuse me? Is my basic understanding incorrect, or is there an error in your algorithm? Thank you.
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