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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
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A surprising fact about quadrilaterals
Interesting tautologies
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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
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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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realhats
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Runge's Phenomenon
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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 ▼
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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
nine men's morris
crochet
runge's phenomenon
statistics
data
correlation
guest posts
braiding
simultaneous equations
javascript
big internet math-off
platonic solids
european cup
weak imposition
thirteen
tennis
hats
rugby
national lottery
go
mathsteroids
crossnumbers
stirling numbers
anscombe's quartet
draughts
bubble bobble
pizza cutting
interpolation
speed
stickers
machine learning
mean
raspberry pi
sorting
menace
christmas card
geogebra
latex
mathslogicbot
crossnumber
golden ratio
golden spiral
football
video games
kings
weather station
fonts
palindromes
world cup
numbers
arrangement puzzles
people maths
bempp
boundary element methods
rhombicuboctahedron
edinburgh
hannah fry
arithmetic
fractals
chalkdust magazine
martin gardner
folding paper
estimation
royal institution
standard deviation
accuracy
hyperbolic surfaces
pi approximation day
zines
gerry anderson
newcastle
graph theory
bluesky
cambridge
pokémon
kenilworth
ternary
chebyshev
dates
asteroids
craft
programming
manchester science festival
rust
finite element method
binary
phd
curvature
polynomials
talking maths in public
triangles
quadrilaterals
turtles
wordle
sport
logic
misleading statistics
coins
matt parker
errors
pac-man
electromagnetic field
manchester
gather town
cross stitch
tetris
game of life
exponential growth
inline code
games
python
graphs
captain scarlet
chess
final fantasy
royal baby
wave scattering
realhats
recursion
fence posts
warwick
london
numerical analysis
countdown
error bars
the aperiodical
databet
sobolev spaces
pythagoras
bots
bodmas
propositional calculus
mathsjam
coventry
php
alphabets
light
pascal's triangle
computational complexity
probability
youtube
preconditioning
books
christmas
noughts and crosses
flexagons
finite group
partridge puzzle
a gamut of games
harriss spiral
24 hour maths
sound
approximation
reddit
folding tube maps
oeis
news
matrices
puzzles
geometry
squares
nonograms
friendly squares
live stream
tmip
pokémon wordle
game show probability
hexapawn
matrix multiplication
datasaurus dozen
matrix of minors
gaussian elimination
reuleaux polygons
logo
convergence
dataset
dinosaurs
determinants
logs
regular expressions
advent calendar
pi
london underground
ucl
wool
dragon curves
radio 4
plastic ratio
trigonometry
data visualisation
inverse matrices
map projections
frobel
crosswords
matrix of cofactors
signorini conditions
© Matthew Scroggs 2012–2026
I initially thought the answers were simply 44×44 = 1936 and 99×99999999 = 9899999901, respectively ????
on /blog/112