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