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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
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A regular expression Christmas puzzle
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Mathsteroids on hyperbolic surfaces
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Build your own MENACE
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Christmas (2020) is coming!
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Happy -2+g-π 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
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Christmas (2018) is over
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▼ show ▼
▲ hide ▲
Dec 2018
Christmas cross stitch
MENACE in fiction
Christmas card 2018
Nov 2018
Christmas (2018) is coming!
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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
graphs
warwick
accuracy
national lottery
chalkdust magazine
golden ratio
pi
pizza cutting
hannah fry
tmip
dinosaurs
latex
rust
dataset
oeis
numbers
braiding
wave scattering
talking maths in public
ucl
matrix of cofactors
noughts and crosses
gaussian elimination
crosswords
javascript
london underground
inverse matrices
pi approximation day
sorting
news
24 hour maths
matrix of minors
game show probability
wool
chess
martin gardner
exponential growth
palindromes
folding tube maps
coventry
matrix multiplication
puzzles
golden spiral
anscombe's quartet
asteroids
numerical analysis
kenilworth
european cup
hexapawn
a gamut of games
royal institution
big internet math-off
realhats
bempp
propositional calculus
radio 4
dragon curves
recursion
estimation
boundary element methods
datasaurus dozen
bodmas
mean
manchester
signorini conditions
sobolev spaces
raspberry pi
pythagoras
london
game of life
countdown
cross stitch
frobel
light
rugby
quadrilaterals
regular expressions
curvature
royal baby
friendly squares
hyperbolic surfaces
thirteen
folding paper
data
statistics
books
christmas
stickers
advent calendar
reddit
flexagons
data visualisation
sound
arithmetic
trigonometry
matt parker
cambridge
the aperiodical
crossnumber
final fantasy
bots
captain scarlet
chebyshev
speed
games
inline code
phd
approximation
world cup
weak imposition
convergence
sport
errors
determinants
electromagnetic field
runge's phenomenon
pac-man
preconditioning
probability
mathslogicbot
edinburgh
fence posts
crochet
squares
dates
logo
geometry
databet
crossnumbers
simultaneous equations
draughts
people maths
nonograms
reuleaux polygons
newcastle
graph theory
youtube
map projections
menace
matrices
platonic solids
triangles
mathsjam
machine learning
kings
christmas card
ternary
logs
finite element method
polynomials
tennis
gather town
craft
harriss spiral
interpolation
alphabets
turtles
standard deviation
pascal's triangle
nine men's morris
video games
binary
logic
correlation
go
mathsteroids
rhombicuboctahedron
coins
error bars
misleading statistics
gerry anderson
guest posts
fonts
finite group
partridge puzzle
hats
manchester science festival
geogebra
stirling numbers
bubble bobble
plastic ratio
zines
weather station
football
live stream
php
python
computational complexity
programming
fractals
© 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