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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
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×1
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PhD thesis, chapter ∞
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Optimal Pac-Man
Tube map stellated rhombicuboctahedron
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friendly squares
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errors
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numbers
a gamut of games
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stirling numbers
youtube
london
squares
cross stitch
hats
newcastle
accuracy
go
bots
runge's phenomenon
speed
determinants
fractals
warwick
mean
24 hour maths
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alphabets
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data visualisation
reddit
the aperiodical
chalkdust magazine
tmip
hexapawn
binary
curvature
inverse matrices
zines
error bars
programming
latex
palindromes
manchester
boundary element methods
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bempp
gather town
estimation
coins
mathsjam
logs
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realhats
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stickers
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geometry
noughts and crosses
folding tube maps
oeis
countdown
manchester science festival
nine men's morris
game show probability
gaussian elimination
books
european cup
menace
numerical analysis
football
simultaneous equations
geogebra
misleading statistics
approximation
pi approximation day
folding paper
frobel
flexagons
plastic ratio
logo
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crossnumber
interpolation
pascal's triangle
ternary
pizza cutting
matrix of cofactors
pac-man
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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