mscroggs
.co.uk
mscroggs
.co.uk
blog
puzzles
academic
talks
contact
subscribe
↓ ☰ ↓
subscribe
Loading image...
Comment
Comments
Comments in green were written by me. Comments in blue were not written by me.
2016-12-20
@
Dan Whitman
: Find the difference between the original number and the reverse of the original. Call this difference \(a\). Next add \(a\) to the reverse of \(a\)...
Matthew
on
/blog/37
×1
2016-12-20
@
Matthew
: Thank you for the prompt response! It makes sense now and perhaps I should have read a little closer!
Dan Whitman
on
/blog/37
Archive
Show me a random blog post
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 -6+τφ 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
draughts
regular expressions
noughts and crosses
reddit
matrix multiplication
coins
accuracy
cambridge
bempp
world cup
crossnumbers
stirling numbers
phd
asteroids
the aperiodical
arrangement puzzles
pokémon
gerry anderson
wave scattering
convergence
mean
php
realhats
boundary element methods
stickers
gather town
recursion
big internet math-off
golden ratio
fonts
logs
advent calendar
geogebra
wordle
youtube
misleading statistics
kings
javascript
mathslogicbot
folding paper
captain scarlet
football
golden spiral
logo
crochet
pi approximation day
24 hour maths
pizza cutting
game show probability
trigonometry
electromagnetic field
plastic ratio
royal institution
interpolation
a gamut of games
crosswords
flexagons
correlation
machine learning
arithmetic
curvature
partridge puzzle
menace
binary
crossnumber
pi
european cup
newcastle
fence posts
kenilworth
hyperbolic surfaces
quadrilaterals
sobolev spaces
nonograms
matrices
national lottery
data visualisation
weather station
errors
puzzles
numbers
edinburgh
preconditioning
fractals
manchester science festival
python
sorting
latex
games
graphs
error bars
chalkdust magazine
pokémon wordle
approximation
video games
hexapawn
raspberry pi
rust
ucl
bodmas
folding tube maps
probability
sound
mathsjam
christmas card
polynomials
data
speed
london underground
cross stitch
propositional calculus
programming
palindromes
squares
rugby
matt parker
dataset
talking maths in public
mathsteroids
exponential growth
weak imposition
simultaneous equations
rhombicuboctahedron
logic
databet
thirteen
runge's phenomenon
platonic solids
inverse matrices
friendly squares
frobel
live stream
bots
radio 4
go
triangles
tetris
dates
coventry
tennis
dragon curves
warwick
statistics
map projections
ternary
datasaurus dozen
royal baby
numerical analysis
harriss spiral
sport
countdown
game of life
light
graph theory
news
bluesky
estimation
books
wool
pac-man
braiding
dinosaurs
zines
chess
signorini conditions
computational complexity
pythagoras
tmip
geometry
pascal's triangle
nine men's morris
craft
finite group
guest posts
hats
anscombe's quartet
matrix of cofactors
inline code
christmas
manchester
turtles
determinants
gaussian elimination
martin gardner
bubble bobble
finite element method
hannah fry
final fantasy
matrix of minors
london
alphabets
chebyshev
people maths
reuleaux polygons
standard deviation
oeis
Archive
Show me a random blog post
▼ show ▼
▲ hide ▲
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 -6+τφ 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
bempp
nonograms
oeis
mathsjam
ucl
hannah fry
realhats
matrix of minors
binary
london
pythagoras
correlation
big internet math-off
folding paper
puzzles
games
dates
datasaurus dozen
live stream
sobolev spaces
noughts and crosses
geogebra
machine learning
pac-man
simultaneous equations
dinosaurs
royal baby
golden spiral
accuracy
dragon curves
christmas card
weak imposition
harriss spiral
programming
php
frobel
zines
runge's phenomenon
finite group
crossnumbers
trigonometry
national lottery
friendly squares
fonts
standard deviation
phd
craft
bots
exponential growth
preconditioning
speed
pokémon wordle
kings
folding tube maps
triangles
boundary element methods
mean
royal institution
manchester science festival
logs
mathslogicbot
football
dataset
partridge puzzle
wool
raspberry pi
inverse matrices
warwick
data
weather station
24 hour maths
matt parker
curvature
rust
fractals
finite element method
european cup
draughts
stickers
arrangement puzzles
asteroids
errors
interpolation
captain scarlet
flexagons
light
christmas
tmip
logo
braiding
recursion
platonic solids
convergence
cambridge
talking maths in public
javascript
video games
bodmas
manchester
sport
rhombicuboctahedron
thirteen
a gamut of games
coins
numbers
coventry
pizza cutting
reddit
numerical analysis
tennis
approximation
pi
alphabets
turtles
probability
reuleaux polygons
london underground
signorini conditions
latex
graphs
geometry
ternary
nine men's morris
hexapawn
mathsteroids
error bars
crochet
fence posts
gerry anderson
gather town
computational complexity
matrix of cofactors
radio 4
guest posts
matrix multiplication
final fantasy
arithmetic
youtube
stirling numbers
wordle
world cup
plastic ratio
statistics
chess
countdown
golden ratio
inline code
edinburgh
sorting
data visualisation
pi approximation day
python
news
hyperbolic surfaces
bluesky
quadrilaterals
map projections
go
anscombe's quartet
logic
game of life
graph theory
pokémon
sound
hats
martin gardner
kenilworth
estimation
pascal's triangle
people maths
misleading statistics
bubble bobble
menace
databet
electromagnetic field
the aperiodical
tetris
crossnumber
polynomials
cross stitch
game show probability
propositional calculus
squares
matrices
gaussian elimination
chalkdust magazine
newcastle
chebyshev
books
palindromes
rugby
regular expressions
determinants
wave scattering
advent calendar
crosswords
© Matthew Scroggs 2012–2026
on /blog/37