mscroggs.co.uk

mscroggs.co.uk

blog puzzles academic talks contact subscribe ↓ ☰ ↓

Comment

Comments

Comments in green were written by me. Comments in blue were not written by me.

2020-01-02

It's interesting that the three puzzles with the most incorrect attempts can all be looked up on OEIS.

Day 15 - https://oeis.org/A001055 - "number of ways of factoring n with all factors greater than 1"

Day 4 - https://oeis.org/A001045 - "number of ways to tile a 2 Ã— (n-1) rectangle with 1 Ã— 2 dominoes and 2 Ã— 2 squares"

Day 2 - https://oeis.org/A002623 - "number of nondegenerate triangles that can be made from rods of length 1,2,3,4,...,n"

Adam Abrams
on /blog/72

×1

Archive

Show me a random blog post

2025

Mar 2025

How to write a crossnumber

Jan 2025

Christmas (2024) is over
Friendly squares

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

Tags

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

Archive

Show me a random blog post
▼ show ▼

© Matthew Scroggs 2012–2025