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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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A nonogram alphabet
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How to write a crossnumber
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Friendly squares
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A regular expression Christmas puzzle
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Logo Asteroids
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Mathsteroids on hyperbolic surfaces
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The databet
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Off-by-one errors
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24 Hour Maths Game Show
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Approximating π
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Build your own MENACE
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Happy -10+e√2+5√3 Approximation Day!
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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
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Visualising MENACE's learning
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A non-converging LaTeX document
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Big Internet Math-Off stickers 2019
Jun 2019
Proving a conjecture
Apr 2019
Harriss and other spirals
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realhats
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Christmas (2018) is over
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Christmas cross stitch
MENACE in fiction
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Christmas (2018) is coming!
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Runge's Phenomenon
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World Cup stickers 2018, pt. 3
Mathsteroids
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World Cup stickers 2018, pt. 2
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A bad Puzzle for Today
Apr 2018
Building MENACEs for other games
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A 20,000-to-1 baby?
World Cup stickers 2018
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Origins of World War I
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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?
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Tube map kaleidocycles
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Solving the cross diagonal cover problem
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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
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Optimal Pac-Man
Tube map stellated rhombicuboctahedron
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Electromagnetic Field talk
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Tennis maths
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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
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Tube map Platonic solids, pt. 2
Oct 2012
Tube map Platonic solids
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Archive
Show me a random blog post
▼ show ▼
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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 -10+e√2+5√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
accuracy
bubble bobble
people maths
rust
data visualisation
go
matrix of cofactors
nonograms
map projections
matrices
crosswords
bots
coins
hannah fry
finite group
polynomials
cross stitch
mathsjam
determinants
nine men's morris
stirling numbers
world cup
fractals
standard deviation
inline code
crossnumber
video games
probability
hyperbolic surfaces
sport
wave scattering
wool
electromagnetic field
sound
anscombe's quartet
logic
squares
live stream
newcastle
warwick
big internet math-off
alphabets
mean
captain scarlet
matrix of minors
gerry anderson
tennis
chebyshev
a gamut of games
crossnumbers
arrangement puzzles
python
folding paper
youtube
manchester
convergence
mathslogicbot
partridge puzzle
correlation
pokémon wordle
pi
advent calendar
triangles
machine learning
graphs
pi approximation day
mathsteroids
graph theory
errors
curvature
fence posts
preconditioning
pokémon
24 hour maths
recursion
finite element method
crochet
data
phd
puzzles
bluesky
platonic solids
london underground
signorini conditions
royal baby
arithmetic
braiding
rhombicuboctahedron
harriss spiral
raspberry pi
chalkdust magazine
logs
ucl
weather station
folding tube maps
golden ratio
pythagoras
christmas card
fonts
realhats
zines
pascal's triangle
dinosaurs
boundary element methods
speed
rugby
dataset
gather town
talking maths in public
coventry
countdown
geogebra
tmip
latex
dragon curves
estimation
games
pac-man
sobolev spaces
reuleaux polygons
sorting
european cup
noughts and crosses
propositional calculus
books
datasaurus dozen
misleading statistics
flexagons
frobel
dates
hexapawn
kenilworth
php
hats
regular expressions
gaussian elimination
football
javascript
craft
databet
thirteen
martin gardner
cambridge
friendly squares
tetris
royal institution
exponential growth
oeis
plastic ratio
wordle
trigonometry
numbers
stickers
computational complexity
interpolation
runge's phenomenon
radio 4
christmas
palindromes
matrix multiplication
geometry
matt parker
news
reddit
national lottery
kings
london
draughts
approximation
simultaneous equations
final fantasy
programming
manchester science festival
bodmas
turtles
menace
weak imposition
edinburgh
chess
ternary
bempp
statistics
the aperiodical
golden spiral
asteroids
light
logo
game show probability
error bars
game of life
binary
guest posts
pizza cutting
inverse matrices
quadrilaterals
numerical analysis
© 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