## Mathiest Fortnight of 2016

*April 7, 2016 at 5:55 am* *
3 comments *

Monday, April 4, 2016, was Square Root Day, because the date is abbreviated 4/4/16, and 4 × 4 = 16. But if you’re a faithful reader of this blog, then you already knew that, because you read all about it in Monday’s post, Guess the Graph on Square Root Day.

But it doesn’t end there. It ain’t just one day. Oh, no, friends… this is a banner week. Or, really, a banner *two weeks*.

Tomorrow, April 8, 2016, is a **geometric sequence day**, because the date is 4/8/16, and 4 × 2 = 8, and 8 × 2 = 16.

And Saturday, April 9, 2016, is a **consecutive square number day**, because the month, day, and year are consecutive square numbers. Square number days, in which each of the month, day, and year are all square numbers — not necessarily consecutive — are less rare; there are 15 of them this year. But among them is 1/4/16, which rocks the intersection of square number days *and* geometric sequence days. (That’s right — I said “rocks the intersection.”)

And then Sunday, April 10, 2016, is an **arithmetic sequence day**, because 4, 10, and 16 have a common difference of 6. Though honestly, arithmetic sequence days are a dime a half-dozen; there are six of them this year.

Next Monday, April 12, 2016, is a **sum day**, because 4 + 12 = 16. Again, ho-hum. There are a dozen sum days this year, and there will be a dozen sum days *every year* through 2031.

And just a little further in the future is Friday, April 16, 2016, whose abbreviation is 4/16/16, and if you remove those unsightly slashes, you get 41,616 = 204^{2}. I’m not sure what you’d call such a day, other than *awesome*.

Admittedly, some of those things are fairly common occurrences. But, still. That’s six calendar-related phenomena in a thirteen-day period, which may be enough mathematic-temporal mayhem to unseat the previously unrivaled Mathiest Week of 2013.

Partially, this blog post was meant to enlighten and entertain you. But mostly, it was meant to send numerologists off the deep end. Mission. Accomplished.

You’ve endured enough. Here are some calendar-related jokes for you…

Did you hear about the two grad students who stole a calendar?

They each got six months!I was going to look for my missing calendar, but I just couldn’t find the time.

What do calendars eat?

Dates.

Entry filed under: Uncategorized. Tags: arithmetic, calendar, dates, geometric, sequence, square.

1.xander | April 7, 2016 at 10:05 amQ: Why are calendars always nervous?

A: Their days are numbered.

x

2.Brooke W | April 22, 2017 at 1:18 pmDid anyone get this calendar puzzle yet, I was solving a calendar day riddle sort of like it and was looking for the answer. I can share that riddle here for you guys as well: How Many Months Have 28 Days

3.venneblock | April 22, 2017 at 4:19 pmHi, Brooke — I’m not sure which calendar puzzle you’re referring to, because there isn’t one in the post to which you attached your comment. Are you asking if anyone has solve the 28 Days puzzle? If so, then the answer’s yes… but I’m not really one to spoil a good puzzle, so I’ll let you solve it on your own.