Happy Pi Day!

Today’s date, March 14, can be written as 3/14, and pi, as some of us will know, is

3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510 …

So of course today I got a cryptic email from hacker king of high weirdness, Bill Gosper.

“Today is the picentennial of January 15, 1693. Various math-fun events of 1693: Newton’s 2nd mental breakdown, 1st published description of fluxions, the 1st publication of Wallis’s *Algebra*, Leibniz rediscovers determinants.” —rwg

I decrypt this as follows.

In Gosperese, “Picentennial” means “The 314.159… year anniversary.” *Bicentennial *is Two * 100 years, right, so *Picentennial *is Pi * 100 years! Now, as 0.159 of a year is 58 days, this in turn means “The 314 years and 58 days anniversary.” And 314 years and 58 days before today, March 14, 2007, would be January 15, 1693.

Although some might raise issues about the change from Julian to Gregorian calendar entailing the notorious 11 skipped days of September, 1752, but any reasonable person should agree that the missing days of 1752 only involve questions about fractions of the year 1752 **itself**.

So today, Pi Day, 2007, is the picentennial of Jan 15, 1693. Party!