# How do I find calendar repetition?

Finding the repetition in a calendar can be a bit tricky, but with a few simple rules, it can be done. The first step is to determine if the year in question is a leap year or a non-leap year. A leap year occurs every four years, with the exception of years divisible by 100 but not divisible by 400. For example, 2000 was a leap year because it is divisible by 400, but 1900 was not because it is divisible by 100 but not by 400.

Once you have determined whether the year is a leap year or a non-leap year, you can proceed to find the repetition. Let’s start with a leap year repetition. In a leap year, the repetition will occur on another leap year. To find this, simply add 4 to the current year. For example, if the current year is 2020 (a leap year), the next leap year repetition will be in 2024.

Now, let’s move on to a non-leap year repetition. In a non-leap year, the repetition will occur on another non-leap year. To find this, add 28 to the current year. However, there is a caveat. If adding 28 to a leap year results in a non-leap year, then you need to add 40 instead. This is because adding 28 years to a leap year will result in a non-leap year, so we need to add an additional 12 years to account for the extra day in a leap year. For example, if the current year is 2021 (a non-leap year), adding 28 would give us 2049, which is also a non-leap year. Therefore, we need to add 40, resulting in a repetition in 2061.

To summarize the steps for finding calendar repetition:

1. Determine if the year is a leap year or a non-leap year.
2. If it is a leap year, add 4 to find the next leap year repetition.
3. If it is a non-leap year, add 28. If the resulting year is a leap year, add 12 more years; otherwise, add 40 to find the next non-leap year repetition.

Here is a practical example to illustrate the process. Let’s say the current year is 2023. First, we determine that 2023 is not a leap year. Next, we add 28 to 2023, which gives us 2051. However, 2051 is a leap year, so we need to add an additional 12 years, resulting in a repetition in 2063.

Finding the calendar repetition involves determining whether the year is a leap year or a non-leap year and then adding the appropriate number of years to find the next repetition. By following the steps outlined above, you can easily calculate the calendar repetition for any given year.