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Comments in green were written by me. Comments in blue were not written by me.
2025-12-18
Question: For the Dec 15 puzzle, does a trivial solution in which the only odd factor is 1 count? Nothing in the text prohibits this currently, but want to make sure this was not just overlooked.
Dan Whitman
on
/blog/120
2025-12-18
@
Dan Whitman
: yes, they count
Matthew
on
/blog/120
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PhD thesis, chapter ∞
PhD thesis, chapter 5
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Inverting a matrix
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Christmas (2017) is over
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Big Ben Strikes Again
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The end of coins of constant width
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The importance of estimation error
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Is MEDUSA the new BODMAS?
2016
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Christmas (2016) is over
Video game surfaces
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Christmas (2016) is coming!
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Logical contradictions
Palindromic dates
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Tube map kaleidocycles
Jul 2016
Solving the cross diagonal cover problem
Jun 2016
Braiding, pt. 2
Braiding, pt. 1
Making names in Life
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Euro 2016 stickers
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Proving Pythagoras' theorem
Dragon curves
The
Mathematical Games
of Martin Gardner
Jan 2016
Christmas (2015) is over
2015
▼ show ▼
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Nov 2015
Christmas (2015) is coming!
Oct 2015
How to kick a conversion
How much will I win on the new National Lottery?
Aug 2015
How OEISbot works
MENACE
Mar 2015
Optimal Pac-Man
Tube map stellated rhombicuboctahedron
Logic bot, pt. 2
Design your own flexagon
Jan 2015
Tube map Platonic solids, pt. 3
2014
▼ show ▼
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Nov 2014
Logic bot
Sep 2014
Electromagnetic Field talk
Jun 2014
Tennis maths
May 2014
World Cup stickers
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Countdown probability, pt. 2
Countdown probability
Mar 2014
New machine unfriendly £1 coin, pt. 2
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2013
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Assorted christmaths
Pointless probability
Jul 2013
"Uncanny" royal coincidence
Raspberry Pi weather station
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Tube map Platonic solids, pt. 2
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Tube map Platonic solids
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countdown
light
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rust
stirling numbers
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puzzles
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coins
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errors
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speed
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oeis
rhombicuboctahedron
fonts
chebyshev
bubble bobble
dragon curves
christmas card
sorting
programming
recursion
folding paper
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go
manchester
hexapawn
london
games
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pokémon wordle
realhats
triangles
geometry
matrix of minors
coventry
geogebra
inverse matrices
final fantasy
reddit
royal institution
matrix of cofactors
databet
preconditioning
books
arrangement puzzles
squares
platonic solids
sport
pi approximation day
error bars
the aperiodical
manchester science festival
dataset
sobolev spaces
propositional calculus
menace
sound
cambridge
news
stickers
london underground
folding tube maps
edinburgh
golden ratio
accuracy
rugby
simultaneous equations
a gamut of games
zines
python
mathsteroids
bots
misleading statistics
electromagnetic field
polynomials
advent calendar
harriss spiral
friendly squares
wordle
fence posts
data visualisation
runge's phenomenon
craft
gather town
tetris
finite element method
game of life
chalkdust magazine
mathsjam
estimation
guest posts
pizza cutting
graph theory
plastic ratio
quadrilaterals
national lottery
correlation
matrix multiplication
nine men's morris
crochet
map projections
palindromes
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mathslogicbot
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big internet math-off
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