Sari Dates...
My daughter Sandy’s friend, Sari, noted on December 16, 2009, that on that particular day, when the date was expressed as 12/16/09, the square of the month equaled the product of the day of the month and the year. That is,
December squared = (the 16th) times (09), or better yet,
I think this is a fun relationship and will give such dates the name Sari Dates. So, of course, we need to know how many Sari Dates there are.
I counted 40 of them. I listed each month and just counted. Here is how.
In general we want to count the number of occurrences of the event
Let’s...