Kat Phillips tumbles down a numerical rabbit hole after a text message from her mother. Extra footage at: https://youtu.be/bIbTfdbQaSE -- More links & stuff in full description below ↓↓↓ More about Kat, including links to her work and streaming and other stuff: https://katdoesmaths.me/ She's on Twitch here: https://twitch.tv/katdoesmaths The entire text message exchange in all its glory can be found on our Patreon: https://www.patreon.com/numberphile/posts/161134605 Every number is the sum of three palindromes: https://youtu.be/OKhacWQ2fCs Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Videos by Brady Haran Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Numberphile creator Brady Haran sees Gerd Faltings receive the Abel Prize - and goes behind the scenes at this prestigious event in Norway. Playlist from the event (with the longer interviews) at https://www.youtube.com/playlist?list=PLt5AfwLFPxWL4w1j3Xc3hZekFUNHGHCfq Abel Prize website: https://abelprize.no/ Abel Prize on YouTube: https://www.youtube.com/channel/UCIJF5m5y70ZQoDCXVq0k50A Numberphile interviews with Fields Medallists: https://www.youtube.com/playlist?list=PLt5AfwLFPxWIDErJihuPX2S7E-0rnkaeu Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Featuring Neil Sloane - more details below. Gear Train (episode sponsor) is at https://www.metmo.co.uk/collections/gear-train with discount code NUMBERPHILE10OFF -- More links & stuff in full description below ↓↓↓ More Neil Sloane videos at: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJXQqPe_llzWmTHMPb9QvV2 Neil Sloane is the founder of the OEIS: https://oeis.org/ Lollipop Numbers: https://oeis.org/A389624 Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran and Pete McPartlan Thanks also to Jonas Karlsson Extra checking by the Numberphile Society - special mention to Debbie and Felipe Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Featuring Neil Sloane, founder of the OEIS... See the extra patterns and variations (including three knights) at https://youtu.be/VgmDuBCayPw More links & stuff in full description below ↓↓↓ With thanks also to Jonas Karlsson - https://jonka364.github.io/ Neil Sloane is the founder of the On-Line Encyclopedia of Integer Sequences - https://oeis.org/ More videos with Neil Sloane: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJXQqPe_llzWmTHMPb9QvV2 See our Trapped Knight video - https://youtu.be/RGQe8waGJ4w More chess-related videos - https://www.youtube.com/playlist?list=PLt5AfwLFPxWKX9OPJqBQTdIOAKthKzQ9m OEIS sequences related to this video: https://oeis.org/A308885 (only black knights) https://oeis.org/A392177 & https://oeis.org/A392178 (red & black knights) https://oeis.org/A395357 (the final spiral) Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Videos by Brady Haran Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Rubik's Cube combinations quickly lead to some unimaginably large numbers. More links & stuff in full description below ↓↓↓ Extra footage on odd-numbered cubes: https://youtu.be/CTb7RyTwoQ0 Featuring Richard Elwes. More Richard on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWI42WXh1jnv51jHrcjatrk8 Rubik's Cube playlist: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJNAdHv8TUCOmj7iKqyHZeg More big numbers on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJ_FwchNAjB3xa8UnoKdmQI More about Richard Elwes (who is based at the University of Leeds): https://richardelwes.co.uk/ Richard's new book Huge Numbers Waterstones (UK): https://www.waterstones.com/book/huge-numbers/richard-elwes/9781399818827 Barnes and Noble (US): https://www.barnesandnoble.com/w/huge-numbers-richard-elwes/1147952914 Or Amazon (affiliate links)... UK: https://amzn.to/4bSZA8v US: https://amzn.to/4v3CIMp Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran & Pete McPartlan Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Hannah Fry returns to Numberphile to showcase her art skills (and show us her new portrait at The Royal Society). See the Objectivity video (for more about the REAL artwork) at https://youtu.be/3HLxB5LbrDU More links & stuff in full description below ↓↓↓ (Real) artist Chloe Barnes can be found at: https://www.chloebarnesartist.com/ (and a handful of limited edition prints of her Hannah portrait were still available at the time we published this video!) Thanks also to artist Paulina Kwietniewska who did the painting of Chloe: https://paulinakwietniewska.com/ The Royal Society collections: https://royalsociety.org/about-us/what-we-do/collections/ Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran and James Hennessy Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

OEIS founder Neil Sloane on lines of primes, awkward primes... and a 'party pooper prime'. More of this interview at https://youtu.be/u-_8wX4cECo Jane Street's puzzle at https://jane-st.co/Numberphile-JS-NumberCross4 and more puzzles at https://jane-st.co/Numberphile-JS-Puzzles More links & stuff in full description below ↓↓↓ SOME RELEVANT OEIS SEQUENCES Lines of Primes: https://oeis.org/A373813 Awkward Primes: https://oeis.org/A393445 More videos with Neil Sloane: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJXQqPe_llzWmTHMPb9QvV2 Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Videos by Brady Haran Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Thanks to ALL our eagle-eyed helpers at The Numberphile Society, especially today to Debbie, Josh and Steven

Richard Elwes discusses the original Big Numbers... long before the likes of Graham's Number and Tree(3). They are epic. More links & stuff in full description below ↓↓↓ More Richard on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWI42WXh1jnv51jHrcjatrk8 More big numbers on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJ_FwchNAjB3xa8UnoKdmQI More about Richard Elwes (who is based at the University of Leeds): https://richardelwes.co.uk/ Richard's new book Huge Numbers Waterstones (UK): https://www.waterstones.com/book/huge-numbers/richard-elwes/9781399818827 Barnes and Noble (US): https://www.barnesandnoble.com/w/huge-numbers-richard-elwes/1147952914 Or Amazon (affiliate links)... UK: https://amzn.to/4bSZA8v US: https://amzn.to/4v3CIMp Here's the mega zoom of Patreon names: https://www.patreon.com/posts/154415033 Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran and Pete McPartlan Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Chief Meteorologist Dan Harris discusses (at length) one of the most famous equations in weather forecasting - the Quasi Geostrophic Omega Equation. More links & stuff in full description below ↓↓↓ Catch our podcast with Dan on podcast players or here on YouTube - https://youtu.be/lnARyhaqMvU Dan works for the Met Office as a chief meteorologist - https://www.metoffice.gov.uk/ Check out some Met Office archive stuff at Brady's Objectivity channel - https://www.youtube.com/playlist?list=PLd5y2WfrtsPrauSfrdFfkE7iZ-KG9pCzO Weather videos on Brady's Sixty Symbols channel - https://www.youtube.com/playlist?list=PLcUY9vudNKBNpsv8AWUvJxbOl6S2pw8so Navier-Stokes Equation video - https://www.youtube.com/watch?v=ERBVFcutl3M Dan's website - https://www.roostweather.com/ Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran and Pete McPartlan Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Tony Padilla calculates Pi with Skittles - then uses UK population data to do the same thing. Results may vary! More links & stuff in full description below ↓↓↓ More Pi videos from Numberphile - https://www.youtube.com/playlist?list=PL4870492ACBDC2E7C More Tony Padilla videos - https://www.youtube.com/playlist?list=PLt5AfwLFPxWL8KAJKO3WfHhJcWrJfjgfU Tony Padilla's book Fantastic Numbers and Where to Find Them - https://amzn.to/3VywNyy Tony is a professor at the University of Nottingham. Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Videos by Brady Haran Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Date formats and other reasons for Pi Day grumpiness from emeritus astronomy professor Mike Merrifield. More links & stuff in full description below ↓↓↓ More Pi videos from Numberphile: https://www.youtube.com/playlist?list=PL4870492ACBDC2E7C Professor Merrifield on Sixty Symbols (our physics channel): https://www.youtube.com/playlist?list=PLcUY9vudNKBNGAgplgACrGL9UlxyDHq7k Professor Merrifield is also a regular on Deep Sky Videos (our astronomy channel): https://www.youtube.com/@DeepSkyVideos Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Videos by Brady Haran Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Matt Parker explains there's a new title-holder for the largest known reversible prime (or Emirp). Learn for free on Brilliant (and get 20% off a premium subscription) at https://brilliant.org/numberphile (episode sponsor) -- More links & stuff in full description below ↓↓↓ Full interview with Stephan Schöler (who discovered the number) - https://youtu.be/Rd8moV7jVX0 Patrons can watch a timelapse of Brady filming Matt for this video - https://www.patreon.com/posts/150828843 More Matt on Numberphile - https://www.youtube.com/playlist?list=PLt5AfwLFPxWKuRpivZd_ivR2EvEzKrDUu MATT PARKER LINKS Website - https://standupmaths.com/ Live shows - https://standupmaths.com/shows/ Books - https://mathsgear.co.uk/collections/books Books on Amazon - https://amzn.to/4rK4j3C Penguin UK: https://www.penguin.co.uk/authors/77633/matt-parker Penguin Random House US: https://www.penguinrandomhouse.com/authors/2198716/matt-parker/ YouTube channel (standupmaths) - https://www.youtube.com/user/standupmaths Prime number playlist: https://www.youtube.com/playlist?list=PL0D0BD149128BB06F Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran and Pete McPartlan Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Ben Sparks explores hidden depths of a seemingly simple game. More on Jane Street's AMP program at https://jane-st.co/Numberphile-AMP-2026 (sponsor) -- More links & stuff in full description below ↓↓↓ An extra snippet on Numberphile2: https://youtu.be/lz2POMYd4YM And a 4.5-minute longer version of this video can be watched by Patrons: https://www.patreon.com/posts/150089653 Ben Sparks own website (you can book him for talks and training, etc): https://www.bensparks.co.uk/ More Ben on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWLDKmnxLg8477hrxY33LL6q The game can be played without the grid at https://15game.bensparks.co.uk/ and can be played with the magic square grid at https://15game.bensparks.co.uk/gameTTT.html Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran and Pete McParlan (who did the stop motion!) Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Ed Copeland goes deep as we explore how we cracked an infinite sum relating to black holes. The extra bit as at https://youtu.be/s8Jd8Z7A5tA -- More links & stuff in full description below ↓↓↓ Ed Copeland is a physics professor at The University of Nottingham More Ed on Numberphile - https://www.youtube.com/playlist?list=PLt5AfwLFPxWJwf-59lYWThTpSj2Ivt5jB Ed on our sister physics channel Sixty Symbols - https://www.youtube.com/playlist?list=PLcUY9vudNKBNtF1y-sneLuyCTE-Mda561 Patreon: http://www.patreon.com/numberphile All our Patreon supporters: https://www.numberphile.com/patrons Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Videos by Brady Haran Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9

Fields Medallist Hugo Duminil-Copin would like a replica of his prize for outreach purposes. We interview him about the famous medal and his mathematical work. More links & stuff in full description below ↓↓↓ Podcast version of the interview: https://youtu.be/jWiKKq_Q5n8 Hugo is based at the University of Geneva and IHES - https://www.ihes.fr/~duminil/ More Numberphile interviews and videos with Fields Medallists - https://www.youtube.com/playlist?list=PLt5AfwLFPxWIDErJihuPX2S7E-0rnkaeu With thanks to Nils Berglund for visualisations of percolation - https://www.youtube.com/c/NilsBerglund Fields Medal 2022 - https://www.mathunion.org/imu-awards/fields-medal/fields-medals-2022 Brady's Zeeman Medal lecture is which he gets his hand on a Fields Medal - https://youtu.be/tsZkzxEhpHk Cedric Villani on his Fields Medal - https://youtu.be/Vp3sgYKULp0 James Maynard on his Fields Medal - https://youtu.be/eupAXdWPvX8 Patreon: http://www.patreon.com/numberphile Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://bit.ly/numberphile-janestreet We are also grateful for support from the Ben Delo Foundation - https://delo.org/ NUMBERPHILE Website: http://www.numberphile.com/ Video by Brady Haran and James Hennessy Numberphile T-Shirts and Merch: https://teespring.com/stores/numberphile Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9