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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 bad Puzzle for Today
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Happy 10+cos(τ) 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
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Inverting a matrix
PhD thesis, chapter 2
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PhD thesis, chapter 1
Gaussian elimination
Matrix multiplication
Christmas (2019) is over
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Visualising MENACE's learning
Christmas card 2019
Nov 2019
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
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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
▼ 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
puzzles
programming
turtles
arithmetic
electromagnetic field
geogebra
regular expressions
gaussian elimination
royal baby
graphs
matrix of cofactors
advent calendar
noughts and crosses
folding paper
exponential growth
simultaneous equations
matt parker
youtube
misleading statistics
pascal's triangle
tennis
javascript
a gamut of games
mean
python
latex
wool
polynomials
london
world cup
approximation
london underground
weak imposition
standard deviation
radio 4
numbers
wave scattering
countdown
inverse matrices
hyperbolic surfaces
nine men's morris
bempp
squares
flexagons
mathsteroids
games
draughts
computational complexity
anscombe's quartet
coins
friendly squares
speed
royal institution
geometry
bubble bobble
game of life
logo
mathslogicbot
game show probability
binary
big internet math-off
bodmas
errors
ucl
recursion
plastic ratio
hats
the aperiodical
accuracy
final fantasy
craft
matrix multiplication
stickers
frobel
weather station
crossnumber
rugby
guest posts
quadrilaterals
captain scarlet
finite element method
pi
triangles
logic
probability
chess
trigonometry
braiding
fractals
palindromes
edinburgh
football
preconditioning
news
gerry anderson
reddit
mathsjam
convergence
logs
zines
live stream
matrices
24 hour maths
runge's phenomenon
data
platonic solids
dinosaurs
talking maths in public
curvature
php
datasaurus dozen
oeis
matrix of minors
cross stitch
people maths
light
rhombicuboctahedron
video games
dragon curves
estimation
data visualisation
european cup
reuleaux polygons
raspberry pi
christmas
sport
signorini conditions
realhats
fonts
chalkdust magazine
go
dates
propositional calculus
graph theory
bots
fence posts
pac-man
sobolev spaces
christmas card
manchester science festival
harriss spiral
folding tube maps
cambridge
pythagoras
newcastle
machine learning
phd
dataset
determinants
golden ratio
numerical analysis
chebyshev
correlation
hannah fry
asteroids
gather town
pizza cutting
manchester
stirling numbers
martin gardner
kings
menace
pi approximation day
statistics
map projections
crochet
interpolation
ternary
books
national lottery
sound
sorting
golden spiral
tmip
hexapawn
finite group
inline code
databet
boundary element methods
error bars
© 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