Numberphile

2012x1
153 and Narcissistic Numbers
Episode overview

We use 153 as an example of a narcissistic number. Video features Dr Ria Symonds from the University of Nottingham.

2012x2
31 and Mersenne Primes
Episode overview

31 is one of the special Mersenne Prime numbers. They are related to perfect numbers.

2012x3
3435
Episode overview

3435 is Matt Parker's "ex" favourite number - but they are still on good terms.

2012x4
15 and Hexadecimal
Episode overview

Why is "f" a number to people who work with computers?

2012x5
98 and Grafting Numbers
Episode overview

Square roots, strange patterns and a mysterious constant - what are Matt's "grafting numbers" all about? And why is computer programming like skydiving?

2012x6
17 and Sudoku Clues
Episode overview

17 is the minimum number of clues required to give a unique sudoku solution - but how did mathematicians prove this?

2012x7
Root 2
Episode overview

The square root of two is a fascinating number with a long and sordid history. It also forms the basis of most office paper, such as A4, A3, etc.

2012x8
3/4 and Kleiber's Law
Episode overview

The fraction three quarters has a particular interest to biologists because of its link to the research of Max Kleiber and metabolic rates in animals.

2012x9
1 And Prime Numbers
Episode overview

Is 1 a prime number? Apparently not. Dr James Grime explains.

2012x10
14 Super Bowl Coin Tosses
Episode overview

The NFC's streak of 14 Super Bowl coin toss wins has come to an end... And they aren't likely to do it again for another 32,766 years. Dr James Grime attempts to calculate how many years - on average - the NFC will wait to win another 14 in a row.

2012x11
7 And Happy Numbers
Episode overview

7 is an example of a happy number, as opposed to sad numbers. What makes a number happy? Dr Ria Symonds is from the University of Nottingham.

2012x12
23 And Football Birthdays
Episode overview

What's the probability that two people on the football/soccer pitch share a birthday? That's only 23 people (22 players and the ref, as long as there have been no red cards or .. show full overview

2012x13
Googol And Googolplex
Episode overview

We're talking pretty big numbers here... And an interesting idea about what it'd be like traveling in a Googolplex-sized Universe! With Antonio (Tony) Padilla and Ria Symonds from the University of Nottingham.

2012x14
Special Magic Square
Episode overview

Magic squares are pretty interesting for Numberphiles any day of the week - but Roger shows us one with extra special "powers". Professor Roger Bowley works at the University of Nottingham.

2012x15
145 And The Melancoil
Episode overview

Matt talks us through "Happification" and resulting structures it creates. Includes his fascinating Melancoil!?

2012x16
1729 and Taxi Cabs
Episode overview

The number 1729 is "famous" among mathematicians. Why? Featuring Dr James Grime and Professor Roger Bowley. 1729 is known as the Hardy--Ramanujan number or "Taxi Cab Number".

2012x17
29 And Leap Years
Episode overview

Astronomer Dr Meghan Gray on leap years and Julian dates. Meghan is making a "guest appearance" on Numberphile and is more familiar to viewers of our sister channels DeepSkyVideos and Sixty Symbols.

2012x18
163 And Ramanujan Constant
Episode overview

Why does Alex Clark, from the University of Leicester, have a strange fascination with 163? Some slightly more advanced stuff in this video, including the Ramanujan Constant and its use in a "famous" April Fool's joke.

2012x19
998,001 And Its Mysterious Recurring Decimals
Episode overview

There has been some internet buzz about 998001, so Numberphile sheds some light on matters. This video features Dr James Grime and we mention the YouTube channel Vsauce.

2012x20
42 And Douglas Adams
Episode overview

Douglas Adams - who would have turned 60 on March 11 - immortalised the number 42 in The Hitchhikers Guide to the Galaxy. Forty-two was calculated by Deep Thought! In this video is James Grime, Phil Moriarty and Gerardo Adesso.

2012x21
Pi
Episode overview

Some stuff about Pi, the "celebrity number'. This video features maths-loving author Alex Bellos (http://alexbellos.com/) and Professor Roger Bowley from the University of Nottingham.

2012x22
Pi And Bouncing Balls
Episode overview

Professor Ed Copeland on a strange occurrence of Pi involving bouncing balls.

2012x23
Pi and Buffon's Matches
Episode overview

Dr Tony Padilla's unique (and low budget) twist on the Buffon's Needle experiment to learn the true value of Pi.

2012x24
Sounds Of Pi
Episode overview

Professor Philip Moriarty attributes some sounds to Pi in a discussion about its randomness and the Feynman Point.

2012x25
5 and Penrose Tiling
Episode overview