mscroggs.co.uk
mscroggs.co.uk

subscribe

Comment

Comments

Comments in green were written by me. Comments in blue were not written by me.
For Day 23, I assume the 3-digit numbers are read top to bottom and left to right?

So the bottom right corner must be odd (the ones digit of an odd number) and it must be even (the ones digit of a multiple of 4)? Isn't that a contradiction if I'm understanding the problem correctly?
Dan
on /blog/69
               

Archive

Show me a random blog post
 2025 

Jan 2025

Christmas (2024) is over
Friendly squares
 2024 
▼ show ▼
 2023 
▼ show ▼
 2022 
▼ show ▼
 2021 
▼ show ▼
 2020 
▼ show ▼
 2019 
▼ show ▼
 2018 
▼ show ▼
 2017 
▼ show ▼
 2016 
▼ show ▼
 2015 
▼ show ▼
 2014 
▼ show ▼
 2013 
▼ show ▼
 2012 
▼ show ▼

Tags

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

Archive

Show me a random blog post
▼ show ▼
© Matthew Scroggs 2012–2025