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Interactive video lesson plan for: The Four 4s - Numberphile

Activity overview:

It was a famous problem for many years - until a physics genius solved it all the way to infinity.
Featuring author Alex Bellos - more links below.

Extras from this interview:

More Numberphile videos with Alex:

Alex's recent book about puzzles (including the Four 4s):
More Alex books:

With a sincere thanks to these Patrons...
Jeff Straathof
Today I Found Out
Peggy You'll
Christian Cooper
Dr Jubal John
James Bissonette
Ken Baron
Andrzej 'Yester' Fiedukowicz
Bill Shillito
Tony Fadell
Erik Alexander Nordlund
Thomas Buckingham
Susan Silver
OK Merli
Tyler O'Connor
Jon Padden
Ciprian Stan
Vali Dobrota
D Hills
Charles Southerland
Paul Bates
Jordan Smith
Tracy Parry
Kristian Joensen
Tryggve Johannesson
Alfred Wallace

Join out Patreon supporters at:

Numberphile is supported by the Mathematical Sciences Research Institute (MSRI):

We are also supported by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of science.

Numberphile on Facebook:
Numberphile tweets:

Videos by Brady Haran

Brady's videos subreddit:

Brady's latest videos across all channels:

Sign up for (occasional) emails:

Tagged under: numberphile, 4s,paul dirac,alex bellos,puzzle

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