I follow Shneer's notation for the Qeviyot. This notation is
(C|L)(D|R|A)(2|3|5|7)
where
C stands for Common year and L stands for a leap year.
D stands for a Deficient (353 or 383 days) year, R stands for Regular (354 or 384 days) year, A stands for Abundant (355 or 385 days) year.
Finally, the number at the end denotes the day in the week Rosh HaShana falls.
For instance, LR3 is a regular leap year (384 days) and it starts on a Tuesday.
For instance, CA2 is abundant common year (355 days) and it starts on a Monday.
