Pi has been calculated to over one trillion digits beyond its decimal point. As an irrational and transcendental number, it will continue infinitely without repetition or pattern. While only a handful of digits are needed for typical calculations, Pi’s infinite nature makes it a fun challenge to memorize, and to computationally calculate more and more digits.
Since 3, 1, and 4 are the first three digits of π in decimal form. The digits appear in this order in the ISO international standard for representing dates (YYYY-MM-DD): 2015-03-14.
Pi Approximation Day is observed on July 22 (or 22/7 in the day/month date format), since the fraction 22⁄7 is a common approximation of Pi, which is accurate to two decimal places and dates from Archimedes.
A sequential time occurs on 3/14/15 at 9:26:53.58979... following the sequence of Pi to all digits, using the America-based system of dating. If the particular date existed, the holiday would be celebrated elsewhere on April 31, as America is the only country that uses the month-first date system.
Bogey, our black Standard Poodle was born on Pi Day. No wonder he's so smart. Happy 13th, Bogey-Boy.