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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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Visualising MENACE's learning
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A non-converging LaTeX document
TMiP 2019 treasure punt
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Big Internet Math-Off stickers 2019
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Proving a conjecture
Apr 2019
Harriss and other spirals
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realhats
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Christmas cross stitch
MENACE in fiction
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Christmas (2018) is coming!
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Runge's Phenomenon
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World Cup stickers 2018, pt. 3
Mathsteroids
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A bad Puzzle for Today
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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 ▼
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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 ▼
▲ hide ▲
Nov 2012
Tube map Platonic solids, pt. 2
Oct 2012
Tube map Platonic solids
Tags
finite element method
exponential growth
hannah fry
final fantasy
go
golden ratio
dinosaurs
graphs
error bars
turtles
fonts
matrices
nonograms
binary
24 hour maths
chess
bots
tetris
realhats
wool
martin gardner
ternary
newcastle
gather town
weak imposition
chalkdust magazine
trigonometry
people maths
databet
numerical analysis
datasaurus dozen
games
inverse matrices
kenilworth
football
quadrilaterals
craft
correlation
advent calendar
speed
warwick
partridge puzzle
sorting
youtube
news
triangles
braiding
game of life
logs
reuleaux polygons
european cup
fractals
phd
statistics
rust
nine men's morris
pokémon wordle
video games
geogebra
folding tube maps
logo
logic
draughts
signorini conditions
standard deviation
coventry
coins
crochet
edinburgh
cambridge
runge's phenomenon
oeis
big internet math-off
crosswords
pi
curvature
mathsteroids
arrangement puzzles
cross stitch
estimation
london
python
electromagnetic field
dragon curves
noughts and crosses
asteroids
errors
javascript
mean
a gamut of games
countdown
mathsjam
folding paper
hyperbolic surfaces
bluesky
accuracy
rhombicuboctahedron
computational complexity
finite group
misleading statistics
christmas card
determinants
dates
reddit
stickers
menace
tmip
christmas
crossnumber
pac-man
tennis
stirling numbers
inline code
flexagons
books
mathslogicbot
alphabets
rugby
platonic solids
pizza cutting
recursion
squares
interpolation
national lottery
gerry anderson
probability
boundary element methods
manchester science festival
light
anscombe's quartet
latex
frobel
preconditioning
data visualisation
wave scattering
sound
royal institution
pascal's triangle
hexapawn
thirteen
game show probability
ucl
pythagoras
php
palindromes
machine learning
hats
chebyshev
geometry
fence posts
data
bodmas
wordle
guest posts
programming
manchester
zines
plastic ratio
harriss spiral
simultaneous equations
raspberry pi
sobolev spaces
golden spiral
dataset
friendly squares
bubble bobble
the aperiodical
polynomials
bempp
numbers
radio 4
captain scarlet
matt parker
puzzles
matrix of cofactors
talking maths in public
sport
propositional calculus
pi approximation day
graph theory
royal baby
world cup
live stream
regular expressions
kings
crossnumbers
matrix of minors
convergence
pokémon
arithmetic
matrix multiplication
map projections
weather station
gaussian elimination
london underground
approximation
© Matthew Scroggs 2012–2026
I initially thought the answers were simply 44×44 = 1936 and 99×99999999 = 9899999901, respectively ????
on /blog/112