---
title: The Immortal Kangaroo Sequence - Numberphile
link: https://www.youtube.com/watch?v=A020pGO5MBs
source: youtube-com-numberphile
published: 2026-09-04T13:06:35Z
updated: 2026-09-05T08:47:40Z
first_seen: 2026-09-08T10:17:10.166315Z
authors:
- Numberphile
summary: |-
  Neil Sloane shares the comma sequence. Then thoughts turn to immortal kangaroos leaping through minefields. More links & stuff in full description below ↓↓↓

  BONUS MATERIAL
  A digital curiosity associated with this video - https://www.patreon.com/numberphile/posts/168587472 (open access)
  BTS timelapse of this video being filmed (Patrons only) - https://www.patreon.com/numberphile/posts/168593344

  See more Neil Sloane videos on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJXQqPe_llzWmTHMPb9QvV2

  Neil is the founder of the On-Line Encyclopedia of Integer Sequences (OEIS): https://oeis.org/

  Some OEIS sequences related to this video...
  Original sequence when we start at 1 - https://oeis.org/A121805
  Landmines: https://oeis.org/A367341
  Numbers where there are two choices: https://oeis.org/A367346
  The infinite path (strictly speaking, it is the lowest infinite path, because there could be more than one): https://oeis.org/A367620
  The sequence of 0's and 1's that lead to immortality (as we know it so far): https://oeis.org/A399179

  Videos from Brady's chemistry trip to Australia (featuring wallabies, kangaroos, and koalas) - https://www.youtube.com/playlist?list=PLD8C8561114777F5A

  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
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---

Neil Sloane shares the comma sequence. Then thoughts turn to immortal kangaroos leaping through minefields. More links & stuff in full description below ↓↓↓

BONUS MATERIAL\
A digital curiosity associated with this video - https://www.patreon.com/numberphile/posts/168587472 (open access)\
BTS timelapse of this video being filmed (Patrons only) - https://www.patreon.com/numberphile/posts/168593344

See more Neil Sloane videos on Numberphile: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJXQqPe\_llzWmTHMPb9QvV2

Neil is the founder of the On-Line Encyclopedia of Integer Sequences (OEIS): https://oeis.org/

Some OEIS sequences related to this video...\
Original sequence when we start at 1 - https://oeis.org/A121805\
Landmines: https://oeis.org/A367341\
Numbers where there are two choices: https://oeis.org/A367346\
The infinite path (strictly speaking, it is the lowest infinite path, because there could be more than one): https://oeis.org/A367620\
The sequence of 0's and 1's that lead to immortality (as we know it so far): https://oeis.org/A399179

Videos from Brady's chemistry trip to Australia (featuring wallabies, kangaroos, and koalas) - https://www.youtube.com/playlist?list=PLD8C8561114777F5A

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