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.
2021-12-23
The version of the card on this page doesn't check if your answers are correct, so it will colour in any number you enter as long as it has the right number of digits.
Matthew
on
/blog/92
×1
Archive
Show me a random blog post
2026
Feb 2026
Christmas (2025) is over
2025
▼ show ▼
▲ hide ▲
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
▼ show ▼
▲ hide ▲
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 1+cos(τ) 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
weak imposition
newcastle
matt parker
people maths
dragon curves
sport
golden ratio
radio 4
london underground
approximation
warwick
mathsteroids
rhombicuboctahedron
pi
reuleaux polygons
a gamut of games
misleading statistics
edinburgh
live stream
pac-man
football
advent calendar
tmip
phd
royal institution
accuracy
the aperiodical
cross stitch
dinosaurs
game of life
datasaurus dozen
kings
dataset
speed
guest posts
hexapawn
noughts and crosses
javascript
chess
go
recursion
weather station
logic
harriss spiral
asteroids
thirteen
graphs
latex
propositional calculus
rugby
python
mean
map projections
big internet math-off
turtles
royal baby
runge's phenomenon
logo
frobel
video games
gather town
chalkdust magazine
platonic solids
sound
machine learning
braiding
gaussian elimination
wave scattering
logs
martin gardner
php
matrices
national lottery
partridge puzzle
oeis
statistics
crossnumber
signorini conditions
estimation
preconditioning
curvature
light
dates
youtube
puzzles
arithmetic
bempp
friendly squares
pascal's triangle
coventry
menace
hats
databet
inline code
manchester science festival
quadrilaterals
standard deviation
pizza cutting
fence posts
hyperbolic surfaces
sobolev spaces
captain scarlet
fractals
boundary element methods
final fantasy
hannah fry
realhats
numerical analysis
pi approximation day
christmas card
cambridge
computational complexity
draughts
graph theory
world cup
games
correlation
golden spiral
mathslogicbot
pythagoras
stirling numbers
zines
rust
chebyshev
nonograms
data
errors
folding paper
ternary
crosswords
polynomials
stickers
squares
european cup
fonts
geogebra
binary
folding tube maps
interpolation
24 hour maths
kenilworth
plastic ratio
tennis
error bars
game show probability
palindromes
flexagons
numbers
sorting
matrix of cofactors
bodmas
alphabets
ucl
regular expressions
news
electromagnetic field
matrix of minors
anscombe's quartet
craft
gerry anderson
matrix multiplication
inverse matrices
coins
geometry
simultaneous equations
triangles
determinants
nine men's morris
christmas
probability
crochet
reddit
raspberry pi
programming
exponential growth
finite group
countdown
talking maths in public
manchester
trigonometry
mathsjam
finite element method
wool
books
crossnumbers
convergence
bubble bobble
london
data visualisation
bots
Archive
Show me a random blog post
▼ show ▼
▲ hide ▲
2026
Feb 2026
Christmas (2025) is over
2025
▼ show ▼
▲ hide ▲
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
▼ show ▼
▲ hide ▲
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 1+cos(τ) 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
folding paper
geometry
guest posts
matrix of cofactors
databet
dinosaurs
finite group
accuracy
weak imposition
books
approximation
quadrilaterals
crossnumbers
simultaneous equations
manchester
coventry
stickers
triangles
bempp
determinants
crosswords
gather town
royal baby
mathsteroids
probability
youtube
palindromes
mathsjam
standard deviation
pi
go
runge's phenomenon
braiding
data
bodmas
christmas card
gaussian elimination
datasaurus dozen
nine men's morris
boundary element methods
kings
recursion
news
alphabets
fence posts
matrices
programming
propositional calculus
dragon curves
binary
speed
zines
game show probability
platonic solids
bubble bobble
world cup
advent calendar
hyperbolic surfaces
stirling numbers
the aperiodical
phd
inline code
asteroids
error bars
mean
coins
fractals
graphs
rust
javascript
realhats
harriss spiral
misleading statistics
pythagoras
puzzles
anscombe's quartet
draughts
chalkdust magazine
mathslogicbot
pi approximation day
craft
talking maths in public
cambridge
python
weather station
friendly squares
game of life
people maths
numerical analysis
captain scarlet
exponential growth
big internet math-off
partridge puzzle
sorting
electromagnetic field
hannah fry
flexagons
plastic ratio
logic
curvature
computational complexity
arithmetic
newcastle
cross stitch
correlation
matt parker
latex
raspberry pi
golden spiral
sobolev spaces
football
golden ratio
estimation
wave scattering
light
data visualisation
machine learning
matrix of minors
national lottery
manchester science festival
fonts
a gamut of games
tennis
pizza cutting
rugby
statistics
frobel
gerry anderson
chebyshev
tmip
bots
pascal's triangle
numbers
countdown
radio 4
squares
inverse matrices
logs
crochet
dates
map projections
video games
trigonometry
sport
final fantasy
regular expressions
rhombicuboctahedron
noughts and crosses
martin gardner
wool
european cup
london underground
graph theory
preconditioning
turtles
finite element method
ternary
hexapawn
signorini conditions
chess
nonograms
php
royal institution
london
menace
dataset
errors
thirteen
folding tube maps
oeis
convergence
warwick
geogebra
24 hour maths
games
ucl
matrix multiplication
polynomials
logo
live stream
reuleaux polygons
christmas
interpolation
reddit
edinburgh
pac-man
kenilworth
crossnumber
sound
hats
© Matthew Scroggs 2012–2026
on /blog/92