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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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Mathsteroids
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A bad Puzzle for Today
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A 20,000-to-1 baby?
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Origins of World War I
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Solving the cross diagonal cover problem
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Braiding, pt. 2
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"Uncanny" royal coincidence
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Off-by-one errors
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Approximating π
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Happy 6+e-√3 Approximation Day!
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A surprising fact about quadrilaterals
Interesting tautologies
Mar 2020
Log-scaled axes
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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
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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
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
light
games
binary
crochet
fractals
regular expressions
plastic ratio
sobolev spaces
stirling numbers
manchester science festival
latex
noughts and crosses
rugby
approximation
reddit
friendly squares
hexapawn
dates
cambridge
databet
statistics
inline code
gaussian elimination
quadrilaterals
edinburgh
folding paper
youtube
books
mathsjam
game of life
logic
fence posts
zines
coins
wool
ternary
weak imposition
royal institution
triangles
matrices
preconditioning
pizza cutting
curvature
braiding
final fantasy
graph theory
puzzles
crossnumber
phd
hannah fry
anscombe's quartet
draughts
go
error bars
javascript
royal baby
nine men's morris
sound
data visualisation
martin gardner
finite element method
national lottery
london
mathsteroids
world cup
stickers
football
dragon curves
hyperbolic surfaces
gerry anderson
guest posts
radio 4
24 hour maths
pi approximation day
craft
datasaurus dozen
dataset
london underground
geometry
dinosaurs
turtles
speed
harriss spiral
signorini conditions
bodmas
correlation
rhombicuboctahedron
boundary element methods
exponential growth
frobel
bubble bobble
chebyshev
flexagons
pi
christmas card
manchester
trigonometry
palindromes
gather town
machine learning
hats
oeis
fonts
wave scattering
european cup
determinants
the aperiodical
sorting
advent calendar
bots
computational complexity
matrix of minors
graphs
numbers
data
matt parker
pascal's triangle
squares
recursion
electromagnetic field
inverse matrices
asteroids
realhats
cross stitch
standard deviation
simultaneous equations
map projections
ucl
talking maths in public
tmip
people maths
logs
kings
misleading statistics
chalkdust magazine
platonic solids
geogebra
captain scarlet
tennis
finite group
game show probability
countdown
numerical analysis
estimation
folding tube maps
golden ratio
logo
errors
pythagoras
chess
christmas
big internet math-off
convergence
menace
newcastle
golden spiral
sport
interpolation
mathslogicbot
probability
mean
matrix multiplication
live stream
video games
matrix of cofactors
accuracy
weather station
news
propositional calculus
polynomials
php
bempp
python
raspberry pi
arithmetic
reuleaux polygons
runge's phenomenon
pac-man
a gamut of games
programming
© Matthew Scroggs 2012–2025
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