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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
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Happy 2+g-φ-5√2 Approximation Day!
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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
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Harriss and other spirals
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realhats
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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
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Origins of World War I
Christmas (2017) is over
2017
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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
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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!
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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 ▼
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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
weather station
pokémon wordle
triangles
approximation
electromagnetic field
graphs
geogebra
gaussian elimination
signorini conditions
computational complexity
php
warwick
advent calendar
partridge puzzle
sport
the aperiodical
squares
matrix of cofactors
friendly squares
simultaneous equations
numerical analysis
pi approximation day
boundary element methods
rhombicuboctahedron
guest posts
hyperbolic surfaces
polynomials
pascal's triangle
frobel
video games
christmas card
rugby
raspberry pi
probability
numbers
chalkdust magazine
mean
captain scarlet
convergence
trigonometry
fractals
dataset
cambridge
manchester science festival
london
sorting
standard deviation
misleading statistics
stickers
asteroids
dates
javascript
london underground
hexapawn
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live stream
puzzles
harriss spiral
pythagoras
dinosaurs
golden spiral
chebyshev
talking maths in public
radio 4
go
nine men's morris
crosswords
european cup
recursion
accuracy
cross stitch
folding paper
zines
finite element method
geometry
craft
royal institution
plastic ratio
sound
python
edinburgh
dragon curves
bempp
crossnumber
palindromes
wordle
world cup
preconditioning
stirling numbers
martin gardner
nonograms
map projections
reddit
coventry
anscombe's quartet
matrix of minors
speed
regular expressions
pi
platonic solids
rust
tetris
crossnumbers
runge's phenomenon
kings
light
pokémon
24 hour maths
hannah fry
finite group
error bars
countdown
bots
gather town
crochet
databet
folding tube maps
bubble bobble
pac-man
braiding
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programming
binary
quadrilaterals
christmas
pizza cutting
matt parker
arrangement puzzles
datasaurus dozen
ucl
logic
logs
graph theory
newcastle
estimation
matrices
bluesky
manchester
youtube
propositional calculus
kenilworth
machine learning
news
national lottery
weak imposition
final fantasy
wool
matrix multiplication
interpolation
statistics
determinants
inline code
noughts and crosses
coins
bodmas
football
realhats
mathsteroids
ternary
exponential growth
hats
oeis
royal baby
sobolev spaces
golden ratio
mathsjam
data visualisation
arithmetic
draughts
errors
curvature
logo
fonts
tennis
correlation
books
data
people maths
a gamut of games
tmip
chess
alphabets
fence posts
mathslogicbot
inverse matrices
reuleaux polygons
menace
wave scattering
big internet math-off
phd
gerry anderson
thirteen
game of life
flexagons
game show probability
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© Matthew Scroggs 2012–2026
I initially thought the answers were simply 44×44 = 1936 and 99×99999999 = 9899999901, respectively ????
on /blog/112