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Comments in green were written by me. Comments in blue were not written by me.
2021-01-03
Happy New Year, one and all!
I think your links point to last year’s calendar puzzles. As for how to solve the puzzle on 21 December,
- permutations of [1,...,n+1] having no substring [k,k+1] - is an option.
(anonymous)
on
/blog/88
2021-01-03
@
(anonymous)
: Thanks, links corrected
Matthew
on
/blog/88
Archive
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The partridge puzzle
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TMiP 2025 puzzle hunt
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A nonogram alphabet
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How to write a crossnumber
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Christmas (2024) is over
Friendly squares
2024
Dec 2024
A regular expression Christmas puzzle
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Zines, pt. 2
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Zines
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TMiP 2023 puzzle hunt
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Chalkdust issue 17
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Logo Asteroids
Mar 2023
Mathsteroids on hyperbolic surfaces
Feb 2023
The databet
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Christmas (2022) is over
2022
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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
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Approximating π
Feb 2022
Build your own MENACE
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Christmas (2021) is over
2021
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Dec 2021
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Close encounters of the second kind
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2020
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Christmas (2020) is coming!
Jul 2020
Happy -62+e+gτ-√3 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
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Dec 2019
Visualising MENACE's learning
Christmas card 2019
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Christmas (2019) is coming!
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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
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Christmas (2018) is over
2018
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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
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Christmas card 2017
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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
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Dec 2016
Christmas (2016) is over
Video game surfaces
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Nov 2016
Christmas (2016) is coming!
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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
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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
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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 ▼
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Dec 2013
Assorted christmaths
Pointless probability
Jul 2013
"Uncanny" royal coincidence
Raspberry Pi weather station
2012
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Nov 2012
Tube map Platonic solids, pt. 2
Oct 2012
Tube map Platonic solids
Tags
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Archive
Show me a random blog post
▼ show ▼
▲ hide ▲
2026
May 2026
World Cup stickers 2026
Apr 2026
A new puzzle every day
Mixing Wordle with other games
Feb 2026
Christmas (2025) is over
2025
Dec 2025
Christmas card 2025
Nov 2025
Christmas (2025) is coming!
Sep 2025
The partridge puzzle
Aug 2025
TMiP 2025 puzzle hunt
Jun 2025
A nonogram alphabet
Mar 2025
How to write a crossnumber
Jan 2025
Christmas (2024) is over
Friendly squares
2024
Dec 2024
A regular expression Christmas puzzle
Christmas card 2024
Nov 2024
Christmas (2024) is coming!
Feb 2024
Zines, pt. 2
Jan 2024
Christmas (2023) is over
2023
▼ show ▼
▲ hide ▲
Dec 2023
Christmas card 2023
Nov 2023
Christmas (2023) is coming!
Zines
Sep 2023
TMiP 2023 puzzle hunt
May 2023
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 ▼
▲ hide ▲
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
▼ show ▼
▲ hide ▲
Dec 2021
Christmas card 2021
Nov 2021
Christmas (2021) is coming!
Sep 2021
TMiP 2021 puzzle hunt
May 2021
Close encounters of the second kind
Jan 2021
Christmas (2020) is over
2020
▼ show ▼
▲ hide ▲
Dec 2020
Christmas card 2020
Nov 2020
Christmas (2020) is coming!
Jul 2020
Happy -62+e+gτ-√3 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
statistics
crossnumber
curvature
puzzles
error bars
chalkdust magazine
errors
final fantasy
matrices
news
graph theory
world cup
interpolation
gerry anderson
folding paper
binary
zines
numerical analysis
datasaurus dozen
latex
geogebra
trigonometry
the aperiodical
inline code
crossnumbers
bodmas
fractals
european cup
talking maths in public
map projections
logo
edinburgh
platonic solids
big internet math-off
golden ratio
mathsjam
accuracy
harriss spiral
convergence
weak imposition
bubble bobble
reuleaux polygons
coventry
stickers
boundary element methods
pi
24 hour maths
crochet
polynomials
regular expressions
cambridge
sobolev spaces
programming
plastic ratio
runge's phenomenon
pokémon
sport
bots
tmip
christmas
captain scarlet
determinants
newcastle
misleading statistics
data visualisation
raspberry pi
weather station
game show probability
pizza cutting
fence posts
london
bempp
london underground
sound
royal institution
exponential growth
graphs
matrix multiplication
games
wave scattering
preconditioning
computational complexity
kenilworth
noughts and crosses
football
speed
hyperbolic surfaces
arrangement puzzles
anscombe's quartet
javascript
squares
cross stitch
turtles
correlation
recursion
countdown
game of life
realhats
oeis
partridge puzzle
books
frobel
matrix of minors
advent calendar
propositional calculus
rhombicuboctahedron
tennis
wool
wordle
estimation
finite group
alphabets
dragon curves
manchester science festival
dataset
chebyshev
reddit
pythagoras
approximation
youtube
go
dates
logic
matrix of cofactors
pascal's triangle
craft
electromagnetic field
warwick
national lottery
probability
standard deviation
thirteen
manchester
quadrilaterals
geometry
people maths
christmas card
coins
numbers
mathsteroids
data
live stream
a gamut of games
crosswords
arithmetic
dinosaurs
gather town
databet
nonograms
golden spiral
finite element method
stirling numbers
video games
rugby
phd
gaussian elimination
mean
hexapawn
ternary
pi approximation day
inverse matrices
nine men's morris
martin gardner
palindromes
braiding
royal baby
matt parker
simultaneous equations
flexagons
radio 4
hats
machine learning
draughts
python
mathslogicbot
rust
guest posts
asteroids
signorini conditions
light
pokémon wordle
friendly squares
triangles
pac-man
chess
fonts
sorting
php
hannah fry
logs
tetris
ucl
bluesky
kings
folding tube maps
menace
© Matthew Scroggs 2012–2026
I think your links point to last year’s calendar puzzles. As for how to solve the puzzle on 21 December, - permutations of [1,...,n+1] having no substring [k,k+1] - is an option.
on /blog/88