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Comments in green were written by me. Comments in blue were not written by me.
2024-12-19
Matt, great card this year! Problems 1 and 2 are slightly ambiguous though in that you did not specify that each digit could only be used once.
I initially thought the answers were simply 44×44 = 1936 and 99×99999999 = 9899999901, respectively ????
Dan Whitman
on
/blog/112
×1
×1
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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
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A non-converging LaTeX document
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Proving a conjecture
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Harriss and other spirals
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Mathsteroids
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A bad Puzzle for Today
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Building MENACEs for other games
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A 20,000-to-1 baby?
World Cup stickers 2018
Jan 2018
Origins of World War I
Christmas (2017) is over
2017
▼ show ▼
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Christmas (2017) is coming!
MENACE at Manchester Science Festival
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Big Ben Strikes Again
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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 ▼
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Nov 2012
Tube map Platonic solids, pt. 2
Oct 2012
Tube map Platonic solids
Tags
talking maths in public
logo
runge's phenomenon
javascript
curvature
graphs
world cup
coventry
alphabets
game show probability
finite element method
mathsteroids
manchester science festival
arrangement puzzles
london underground
sobolev spaces
people maths
gather town
probability
dates
stickers
final fantasy
craft
frobel
big internet math-off
numerical analysis
asteroids
computational complexity
gerry anderson
geogebra
weather station
european cup
menace
reuleaux polygons
matrices
bubble bobble
hexapawn
thirteen
errors
fence posts
manchester
tmip
trigonometry
dragon curves
go
cambridge
graph theory
golden spiral
advent calendar
light
pac-man
preconditioning
exponential growth
mean
programming
folding tube maps
geometry
video games
boundary element methods
youtube
folding paper
bempp
chess
inline code
tetris
signorini conditions
captain scarlet
pokémon wordle
polynomials
christmas
radio 4
kings
flexagons
royal baby
latex
pascal's triangle
determinants
crochet
hyperbolic surfaces
gaussian elimination
logs
machine learning
numbers
football
finite group
pizza cutting
the aperiodical
sorting
rust
noughts and crosses
martin gardner
phd
logic
speed
bluesky
newcastle
books
news
data
databet
statistics
braiding
ternary
matt parker
wordle
games
sport
chalkdust magazine
regular expressions
game of life
nine men's morris
countdown
national lottery
electromagnetic field
arithmetic
rugby
propositional calculus
crossnumber
coins
weak imposition
crossnumbers
hats
realhats
dinosaurs
error bars
draughts
puzzles
tennis
plastic ratio
accuracy
recursion
ucl
inverse matrices
christmas card
sound
oeis
rhombicuboctahedron
partridge puzzle
wool
london
estimation
crosswords
python
royal institution
stirling numbers
friendly squares
fonts
data visualisation
approximation
standard deviation
wave scattering
chebyshev
golden ratio
kenilworth
matrix of cofactors
anscombe's quartet
24 hour maths
interpolation
dataset
binary
correlation
bots
reddit
harriss spiral
triangles
mathsjam
matrix of minors
edinburgh
datasaurus dozen
nonograms
simultaneous equations
live stream
platonic solids
bodmas
pi approximation day
quadrilaterals
raspberry pi
palindromes
turtles
pi
fractals
cross stitch
php
misleading statistics
hannah fry
squares
mathslogicbot
guest posts
pythagoras
matrix multiplication
convergence
zines
pokémon
map projections
warwick
a gamut of games
© Matthew Scroggs 2012–2026
I initially thought the answers were simply 44×44 = 1936 and 99×99999999 = 9899999901, respectively ????
on /blog/112