• **The most recent homepage to explore Pi (π)**: https://81018.com/continuity-symmetry-harmony/

• **Getting beyond our high school understanding**: https://81018.com/starts-2

• **Pi Day 2023** and **UNESCO’s International Day of Mathematics**

• **Pi Day, March 14, 2021**

• **Pi (π) Shapes Our Universe**

• Let’s start at the very beginning as our universe is filling with spheres

• Sphere: Our most basic building block

• Pi Day 2019 Homepage

• Pi Day 2018 Homepage

• Pi Overview

• Pi working page

## Pi equals

## 3.14159265358979323846264338327950288419716939937510…

An arc of a circle with the same length as the radius of that circle corresponds to an *angle* of 1 radian.

A full circle corresponds to an angle of 2π radians.

# Currently Pi equals

**3.14159265358979323846264338327950288419716939937510**… plus in November 2017

- Peter Trueb, after 105 days of non-stop calculations emerged with 22,459,157,718,361 fully verified digits of pi. That is over 22 trillion digits!
- Emma Haruka Iwao ran her computers from September 22, 2018 to January 21, 2019 to emerge with 31.415 trillion units. She then continued and it is now over 100-trillion digits.
- Newton calculated 17 and 17 digits is enough for most applications.

More facts (not guesses):

- Pi ( π ) is the exact ratio of the circumference of a circle to its diameter.
**Pi is a constant**.- Pi is an
**irrational**number. - Pi is a
**transcendental**number. - Pi is a
**non-repeating**number – no pattern has been identified using computer analysis within over twelve trillion places. - Pi is a
**never-ending**number. - Pi within any equation makes the result irrational, never ending and never repeating.
- Pi is a dimensionless constant. It is a mathematical constant.
- Pi is the simplest, most commonly-used dimensionless constant.
- Pi is the bridge between the finite and the infinite.
- The sphere is the first manifestation of spacetime defined by primordial spheres. The Planck Length and Planck Time are approximations of the smallest units of both.
- 2
*π*theorem - Approximations of
*π* - Arithmetic–geometric mean
- Bailey–Borwein–Plouffe formula
- Basel problem
- Borwein’s algorithm
- Buffon’s needle
- Cadaeic Cadenza
- Chronology of computation of
*π* - Circle
- Euler’s identity
- Six nines in pi
- Gauss–Legendre algorithm
- Gaussian function
- History of
*π* *A History of Pi*(book)- Indiana Pi Bill
- Leibniz formula for pi
- Lindemann–Weierstrass theorem (Proof that
*π*is transcendental) - List of circle topics
- List of formulae involving
*π* - Liu Hui’s
*π*algorithm - Mathematical constant (sorted by continued fraction representation)
- Mathematical constants and functions
- Method of exhaustion
- Milü
- Pi
- Pi (art project)
- Pi (letter)
- Pi Day
- PiFast
- PiHex
- Pi in the Sky
- Pilish
- Pimania (computer game)
- Piphilology
- Proof that
*π*is irrational - Proof that 22/7 exceeds
*π* - Proof of Wallis product
- Rabbi Nehemiah
- Radian
- Ramanujan–Sato series
- Rhind Mathematical Papyrus
- Salamin–Brent algorithm
- Software for calculating
*π* - Squaring the circle
- Turn (geometry)
- Viète’s formula

# We also believe…

This page was started in 2012.

# Thank you, Wikipedia…

for the graphics (above) that demonstrate the simple definition.

# Over 45 Wikipedia articles about pi

So, what do you make of it? What is going on? Our continued discussion…