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Comments in green were written by me. Comments in blue were not written by me.
2020-01-02
It's interesting that the three puzzles with the most incorrect attempts can all be looked up on OEIS.
Day 15 -
https://oeis.org/A001055
- "number of ways of factoring n with all factors greater than 1"
Day 4 -
https://oeis.org/A001045
- "number of ways to tile a 2 × (n-1) rectangle with 1 × 2 dominoes and 2 × 2 squares"
Day 2 -
https://oeis.org/A002623
- "number of nondegenerate triangles that can be made from rods of length 1,2,3,4,...,n"
Adam Abrams
on
/blog/72
×1
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Log-scaled axes
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PhD thesis, chapter ∞
PhD thesis, chapter 5
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PhD thesis, chapter 1
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Proving a conjecture
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Runge's Phenomenon
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Mathsteroids
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A bad Puzzle for Today
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Tube map kaleidocycles
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Solving the cross diagonal cover problem
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Braiding, pt. 2
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Making names in Life
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Euro 2016 stickers
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Proving Pythagoras' theorem
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Optimal Pac-Man
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Design your own flexagon
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Logic bot
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Electromagnetic Field talk
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Tennis maths
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World Cup stickers
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Countdown probability, pt. 2
Countdown probability
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New machine unfriendly £1 coin, pt. 2
New machine unfriendly £1 coin
2013
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Assorted christmaths
Pointless probability
Jul 2013
"Uncanny" royal coincidence
Raspberry Pi weather station
2012
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Tube map Platonic solids, pt. 2
Oct 2012
Tube map Platonic solids
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inline code
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How to write a crossnumber
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Dec 2024
A regular expression Christmas puzzle
Christmas card 2024
Nov 2024
Christmas (2024) is coming!
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Zines, pt. 2
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Christmas (2023) is over
2023
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Nov 2023
Christmas (2023) is coming!
Zines
Sep 2023
TMiP 2023 puzzle hunt
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Chalkdust issue 17
Apr 2023
Logo Asteroids
Mar 2023
Mathsteroids on hyperbolic surfaces
Feb 2023
The databet
Jan 2023
Christmas (2022) is over
2022
▼ show ▼
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Dec 2022
Off-by-one errors
Christmas card 2022
Nov 2022
Christmas (2022) is coming!
Oct 2022
24 Hour Maths Game Show
Mar 2022
Approximating π
Feb 2022
Build your own MENACE
Jan 2022
Christmas (2021) is over
2021
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Dec 2021
Christmas card 2021
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Christmas (2021) is coming!
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May 2021
Close encounters of the second kind
Jan 2021
Christmas (2020) is over
2020
▼ show ▼
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Dec 2020
Christmas card 2020
Nov 2020
Christmas (2020) is coming!
Jul 2020
Happy 5+e-φ+√2 Approximation Day!
May 2020
A surprising fact about quadrilaterals
Interesting tautologies
Mar 2020
Log-scaled axes
Feb 2020
PhD thesis, chapter ∞
PhD thesis, chapter 5
PhD thesis, chapter 4
PhD thesis, chapter 3
Inverting a matrix
PhD thesis, chapter 2
Jan 2020
PhD thesis, chapter 1
Gaussian elimination
Matrix multiplication
Christmas (2019) is over
2019
▼ show ▼
▲ hide ▲
Dec 2019
Visualising MENACE's learning
Christmas card 2019
Nov 2019
Christmas (2019) is coming!
Sep 2019
A non-converging LaTeX document
TMiP 2019 treasure punt
Jul 2019
Big Internet Math-Off stickers 2019
Jun 2019
Proving a conjecture
Apr 2019
Harriss and other spirals
Mar 2019
realhats
Jan 2019
Christmas (2018) is over
2018
▼ show ▼
▲ hide ▲
Dec 2018
Christmas cross stitch
MENACE in fiction
Christmas card 2018
Nov 2018
Christmas (2018) is coming!
Sep 2018
Runge's Phenomenon
Jul 2018
World Cup stickers 2018, pt. 3
Mathsteroids
Jun 2018
World Cup stickers 2018, pt. 2
May 2018
A bad Puzzle for Today
Apr 2018
Building MENACEs for other games
Mar 2018
A 20,000-to-1 baby?
World Cup stickers 2018
Jan 2018
Origins of World War I
Christmas (2017) is over
2017
▼ show ▼
▲ hide ▲
Dec 2017
Christmas card 2017
Nov 2017
Christmas (2017) is coming!
MENACE at Manchester Science Festival
Jun 2017
Big Ben Strikes Again
Mar 2017
The end of coins of constant width
Dragon curves II
Feb 2017
The importance of estimation error
Jan 2017
Is MEDUSA the new BODMAS?
2016
▼ show ▼
▲ hide ▲
Dec 2016
Christmas (2016) is over
Video game surfaces
Christmas card 2016
Nov 2016
Christmas (2016) is coming!
Oct 2016
Logical contradictions
Palindromic dates
Sep 2016
Tube map kaleidocycles
Jul 2016
Solving the cross diagonal cover problem
Jun 2016
Braiding, pt. 2
Braiding, pt. 1
Making names in Life
May 2016
Euro 2016 stickers
Mar 2016
Proving Pythagoras' theorem
Dragon curves
The
Mathematical Games
of Martin Gardner
Jan 2016
Christmas (2015) is over
2015
▼ show ▼
▲ hide ▲
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 ▼
▲ hide ▲
Nov 2014
Logic bot
Sep 2014
Electromagnetic Field talk
Jun 2014
Tennis maths
May 2014
World Cup stickers
Apr 2014
Countdown probability, pt. 2
Countdown probability
Mar 2014
New machine unfriendly £1 coin, pt. 2
New machine unfriendly £1 coin
2013
▼ show ▼
▲ hide ▲
Dec 2013
Assorted christmaths
Pointless probability
Jul 2013
"Uncanny" royal coincidence
Raspberry Pi weather station
2012
▼ show ▼
▲ hide ▲
Nov 2012
Tube map Platonic solids, pt. 2
Oct 2012
Tube map Platonic solids
Tags
cross stitch
estimation
crosswords
talking maths in public
finite element method
error bars
javascript
hannah fry
map projections
chalkdust magazine
inline code
logs
football
fence posts
hexapawn
crochet
numbers
tmip
graph theory
anscombe's quartet
big internet math-off
errors
sorting
final fantasy
latex
matt parker
national lottery
game show probability
php
manchester
approximation
light
pizza cutting
convergence
craft
royal baby
matrix of cofactors
data
london
oeis
weather station
finite group
programming
arithmetic
video games
people maths
determinants
weak imposition
gather town
flexagons
the aperiodical
world cup
fractals
reddit
puzzles
ucl
manchester science festival
royal institution
geogebra
fonts
tennis
games
simultaneous equations
pascal's triangle
advent calendar
mathsteroids
data visualisation
matrix multiplication
noughts and crosses
zines
martin gardner
european cup
golden spiral
trigonometry
ternary
nine men's morris
plastic ratio
preconditioning
pi approximation day
inverse matrices
24 hour maths
polynomials
databet
christmas card
matrix of minors
raspberry pi
rhombicuboctahedron
signorini conditions
mathslogicbot
draughts
pac-man
matrices
guest posts
platonic solids
news
go
a gamut of games
menace
regular expressions
youtube
asteroids
wave scattering
books
game of life
coins
radio 4
pi
machine learning
sound
turtles
mathsjam
folding paper
recursion
reuleaux polygons
bubble bobble
sport
stickers
frobel
crossnumbers
golden ratio
captain scarlet
dragon curves
statistics
bempp
mean
computational complexity
wool
numerical analysis
exponential growth
runge's phenomenon
countdown
correlation
gaussian elimination
dates
electromagnetic field
standard deviation
dinosaurs
python
interpolation
accuracy
phd
curvature
probability
gerry anderson
rugby
binary
misleading statistics
friendly squares
crossnumber
datasaurus dozen
bodmas
palindromes
chebyshev
graphs
geometry
london underground
chess
triangles
christmas
dataset
boundary element methods
bots
newcastle
folding tube maps
live stream
pythagoras
squares
edinburgh
quadrilaterals
braiding
hyperbolic surfaces
sobolev spaces
speed
propositional calculus
stirling numbers
cambridge
logo
logic
realhats
harriss spiral
hats
kings
© Matthew Scroggs 2012–2025
Day 15 - https://oeis.org/A001055 - "number of ways of factoring n with all factors greater than 1"
Day 4 - https://oeis.org/A001045 - "number of ways to tile a 2 × (n-1) rectangle with 1 × 2 dominoes and 2 × 2 squares"
Day 2 - https://oeis.org/A002623 - "number of nondegenerate triangles that can be made from rods of length 1,2,3,4,...,n"
on /blog/72