mscroggs.co.uk
mscroggs.co.uk

subscribe

Comment

Comments

Comments in green were written by me. Comments in blue were not written by me.
@Blake: there is an elegant solution but it is very different from day 14. If a small hint is allowed:

recurrence relations!
Aisha
on /blog/120
               
@Aisha: Thanks! I did think of that originally but even going back now I can’t seem to find a neat way to apply that approach (and even the OEIS doesn’t seem to give one for the sequence I get solving this for smaller cases). Would be interested to know how you went about this! As it happens, with a bit more thought I did end up finding a single (double-summation) formula that could be used to calculate this
Blake
on /blog/120
               
@Aisha: Hm, I used exactly the same method for both of these days. I'm not sure if it lends itself to a nice clean formula, but it might! I'll share my approach after the contest is over!
Seth Cohen
on /blog/120
               

Archive

Show me a random blog post
 2026 

May 2026

World Cup stickers 2026

Apr 2026

A new puzzle every day
Mixing Wordle with other games

Feb 2026

Christmas (2025) is over
 2025 

Dec 2025

Christmas card 2025

Nov 2025

Christmas (2025) is coming!

Sep 2025

The partridge puzzle

Aug 2025

TMiP 2025 puzzle hunt

Jun 2025

A nonogram alphabet

Mar 2025

How to write a crossnumber

Jan 2025

Christmas (2024) is over
Friendly squares
 2024 

Dec 2024

A regular expression Christmas puzzle
Christmas card 2024

Nov 2024

Christmas (2024) is coming!

Feb 2024

Zines, pt. 2

Jan 2024

Christmas (2023) is over
 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

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

Archive

Show me a random blog post
▼ show ▼
© Matthew Scroggs 2012–2026