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December 2018

[338] Gaussian Curvature: the Theorema Egregium
[337] Consider a Spherical Christmas Tree
[336] The 3 : 2 Resonance between Neptune and Pluto
[335] Random Numbers Plucked from the Atmosphere

November 2018

[334] The Two Envelopes Fallacy
[333] Gravitational Waves & Ringing Teacups
[332] The “Napoleon of Crime” and The Laws of Thought
[331] Listing the Rational Numbers III: The Calkin-Wilf Tree
[330] Johannes Kepler and the Song of the Earth

October 2018

[329] Saving Daylight with Hip-hop Time: a Modest Proposal
[328] Who Uses Maths? Almost Everyone!
[327] Listing the Rational Numbers II: The Stern-Brocot Tree
[326] The Many Modern Uses of Quaternions

September 2018

[325] Listing the Rational Numbers: I. Farey Sequences
[324] Tom Lehrer: Comical Musical Mathematical Genius
[323] A Trapezoidal Prism on the Serpentine
[322] Face Recognition

August 2018

[321] A Zero-Order Front
[320] The Flight of the Bumble Bee
[319] The Miraculous Spiral on Booterstown Strand
[318] Euler’s “Degree of Agreeableness” for Musical Chords
[317] Tides: a Tug-of-War between Earth, Moon and Sun

July 2018

[316] Grandi’s Series: A Second Look
[315] The Empty Set is Nothing to Worry About
[314] Grandi’s Series: Divergent but Summable
[313] Trigonometric Comfort Blankets on Hilltops

June 2018

[312] Numbers with Nines
[311] Optical Refinements at the Parthenon
[310] “Dividends and Divisors Ever Diminishing”
[309] Leopold Bloom’s Arithmetical Adventures

May 2018

[308] Motifs: Molecules of Music
[307] A Glowing Geometric Proof that Root-2 is Irrational
[306] Mathematics at the Science Museum
[305] Marden’s Marvel
[304] Stan Ulam, a mathematician who figured how to initiate fusion

April 2018

[303] Waves Packed in Envelopes
[302] Geodesics on the Spheroidal Earth-II
[301] Geodesics on the Spheroidal Earth – I
[300] Fourier’s Wonderful Idea – II

March 2018

[299] Fourier’s Wonderful Idea – I
[298] Sophus Lie
[297] Cubic Skulduggery & Intrigue
[296] Subtract 0 and divide by 1
[295] Reducing R-naught to stem the spread of Epidemics

February 2018

[294] The Evolute: Envelope of Normals
[293] Galileo’s Book of Nature
[292] Hardy’s Apology
[291] Staying Put or Going with the Flow

January 2018

[290] Kaprekar’s Number 6174
[289] The Heart of Mathematics
[288] Moebiquity: Ubiquity and Versitility of the Möbius Band
[287] Energy Cascades in Van Gogh’s Starry Night

December 2017
[286] Doughnuts and Tonnetze
[285] Darker Mornings, Brighter Evenings

[284] Vanishing Hyperballs

[283] The Star of Bethlehem … or was it a Planet?

November 2017
[282] Disentangling Loops with an Ambient Isotopy
[281] A Symbol for Global Circulation
[280] Slingshot Orbit to Asteroid Bennu
[279] More on Moduli
[278] Modular Arithmetic: from Clock Time to High Tech

October 2017
[277] Malfatti’s Circles
[276] Learning Maths has never been Easier
[275] Pedro Nunes and Solar Retrogression
[274] From Sailing on a Rhumb to Flying on a Geodesic

September 2017
[273] Building Moebius Bands
[272] Andrey Markov’s Brilliant Ideas are still a Driving Force
[271] Moessner’s Magical Method
[270] Euler and the Fountains of Sanssouci

August 2017
[269] Drawing Multi-focal Ellipses: The Gardener’s Method
[268] Locating the HQ with Multi-focal Ellipses  
[267] Saros 145/22: The Great American Eclipse  
[266] Fractions of Fractions of Fractions  
[265] It’s as Easy as Pi

July 2017
[264] Who First Proved that C / D is Constant?
[263] Quadrivium: The Noble Fourfold Way  
[262] Inertial Oscillations and Phugoid Flight
[261] Robert Murphy, a “Brilliant Meteor”  

June  2017
[260] Patterns in Poetry, Music and Morse Code
[259] The Beer Mat Game
[258] Fractal Complexity of Finnegans Wake
[257] A Remarkable Pair of Sequences
[256] Beautiful Patterns in Maths and Music

May  2017

[255] Wavelets: Mathematical Microscopes
[254] Yves Meyer wins 2017 Abel Prize
[253] Hearing Harmony, Seeing Symmetry
[252] When Roughly Right is Good Enough

April  2017

[251] A Geometric Sieve for the Prime Numbers
[250] The Water is Rising Fast
[249] Torricelli’s Trumpet & the Painter’s Paradox
[248] The Improbability Principle

March  2017

[247] Treize: A Card-Matching Puzzle
[246] Numerical Coincidences
[245] A Life-saving Whirligig
[244] Brun’s Constant and the Pentium Bug 
[243] Enigmas of Infinity

February  2017

[242] Topology in the Oval Office
[241] The Spire of Light
[240] Metallic Means
[239] Voronoi Diagrams: Simple but Powerful

January  2017

[238] The Beginning of Modern Mathematics
[237] The Library of Babel and the Information Explosion
[236] On Knots and Links
[235] The Citizens’ Assembly: Why do 10 Counties have no Members? 

December  2016

[234] Unsolved: the Square Peg Problem
[233] Twenty Heads in Succession: How Long will we Wait?
[232] The Edward Worth Library: a Treasure Trove of Maths
[231] Raphael Bombelli’s Psychedelic Leap
[230] The Shaky Foundations of Mathematics 

November  2016

[229] Taylor Expansions from India
[228] Marvellous Merchiston’s Logarithms
[227] Which is larger, e^pi or pi^e?
[226] A New Window on the World 

October 2016

[225] That’s Maths Book Published
[224] Thank Heaven for Turbulence
[223] Kepler’s Magnificent Mysterium Cosmographicum
[222] A Ton of Wonders An ode to the number 100

September 2016

[221] Negative Number Names 
[220] Venn Again’s Awake  Diagrams for more than three sets
[219] The next Hamilton The chance effects of education
[218] Heron’s Theorem: a Tool for Surveyors No angles needed!
[217] The Tunnel of Eupalinos in Samos A remarkable engineering achievement

August 2016

[216] Slicing Doughnuts 
[215] Recreational Mathematics is Fun Enjoy it.
[214] A Toy Example of RSA Encryption
[213] Can Mathematics Keep Us Secure?

July 2016

[212] Random Harmonic Series
[211] Computers Speaking in Irish
[210] Squircles
[209] Lateral Thinking in Mathematics Simpler from another angle

June 2016

[208] Lecture sans paroles: the factors of M67
[207] Bending the Rules to Square the Circle
[306] Bloom’s attempt to Square the Circle
[205] Prime Generating Formulae
[204] Big Data: the Information Explosion

May 2016

[203] Mathematics Everywhere In Blackrock Station
[202] Andrew Wiles wins 2016 Abel Prize
[201] Ramanujan’s Astonishing Knowledge of 1729
[200] Modelling Rogue Waves

April 2016

[199] Sigmoid Functions: Gudermannian and Gompertz Curves
[198] The Inexorable Rise in Life Expectancy
[197] The Power Tower Fractal
[196] The Search is on for Planet Nine

March 2016

[195] The Imaginary Power Tower: Part II
[194] The Imaginary Power Tower: Part I
[193] Computus: Dating the Resurrection
[192] Peano Music Axioms for natural numbers
[191] The Abel Prize The Nobel Prize for Mathematics

February 2016

[190] Bertrand’s Chord Problem
[189] Vanishing Zigzags of Unbounded Length
[188] Franc-carreau or Fair-square
[187] The Mathematics of Voting

January 2016

[186] Prime Number Record Smashed Again Another Mersenne prime
[185] Entropy Piano Tuning
[184]Twin Peaks
[183] Richardson’s Forecast Factory

December 2015

[182] Squaring the Circular Functions
[181] Factorial 52: A Stirling Problem
[180] How many Christmas Gifts?
[179] The Ping Pong Pendulum
[178] The Flight of a Golf Ball

November 2015

[177] Life’s a Drag Crisis
[176] Mathematics Solving Crimes
[175] Numbering the Family Tree
[174] Melencolia: An Enigma for Half a Millennium

October 2015

[173] Mowing the Lawn in Spirals
[172]A Few Wild Functions
[171] It’s a Small – Networked – World
[170] Which Way did the Bicycle Go?
[169] New Tricks: No Clicks

September 2015

[168] Hamming’s Smart Error-correcting Codes
[167] The Ubiquitous Cycloid
[166] Holbein’s Anamorphic Skull
[165] James Joseph Sylvester

August 2015

[164] Thomas Harriot: Mathematician, Astronomer and Navigator
[163] The Great American Eclipse:
[162] Buffon was no Buffoon
[161] The Bridges of Paris

July 2015

[160] Who Needs EirCode?
[159] Bent Coins: What are the Odds?
[158] RT60 and Acoustic Excellence
[157] Fun and Games on a Honeycombed Rhomboard.
[156] Pluto’s Unruly Family

June 2015

[155] Increasingly Abstract Algebra
[154] Emmy Noether’s beautiful theorem
[153] Game Theory & Nash Equilibrium
[152] The Tragic Demise of a Beautiful Mind

May 2015

[151] Maps on the Web
[150] Mercator’s Marvellous Map
[149] Eccentric Pizza Slices
[148] Modelling the Markets

April 2015

[147] Brouwer’s Fixed-Point Theorem
[146] Tap-tap-tap the Cosine Button
[145] For Good Comms, Leaky Cables are Best
[144] The Hodograph
[143] Mode-S: Aircraft Data improves Weather Forecasts

March 2015

[142] Golden Moments
[141] You Can Do Maths
[140] A King of Infinite Space: Euclid I.
 Euclid organized and systematized geometry.

[139] Café Mathematics in Lvov:

February 2015

[138] The Birth of Functional Analysis:
[137] MGP: Tracing our Mathematical Ancestry:
[136] The Klein 4-Group:
[135] Perelman’s Theorem: Who Wants to be a Millionaire?

January 2015

[134] The Steiner Minimal Tree:
[133] Plateau’s Problem and Double Bubbles:
[132] Barcodes and QR Codes:
[131] Seifert Surfaces for Knots and Links:
[130] The MacTutor Archive:
[129] 2014 in review:

December 2014

[128] Fermat’s Christmas Theorem:
[127] Information Theory: The wide implications of
[126] New Curves for Old:
[125] The Year of George Boole:

November 2014

[124] Falling Bodies [2]:
[123] Earth’s Shape and Spin Won’t Make You Thin:
[122] Falling Bodies [1]: Sky-diving: Slowing down as you fall farther.
[121] El Niño likely this Winter:

October 2014

[120] Light Weight (*):
[119] Waring’s Problem & Lagrange’s Four-Square Theorem.
[118] Old Octonions may rule the World: Numbers discovered by
[117] Triangular Numbers: EYPHKA:
[116] Algebra in the Golden Age:

September 2014

[115] Curves with Singularities:
[114] How Big was the Bomb?
[113] Cartoon Curves:
[112] The Biggest Harp in Ireland: Music on a Liffey Bridg

August 2014

[111] Temperamental Tuning: Musical structure and t
[110] Biomathematics: the New Frontier:
[109] Do you remember Venn?
[108] “Come See the Spinning Globe”:

July 2014

[107] Degrees of Infinity:
[106] Invention or Discovery?
[105] Digital Dentistry:
[104] Gauss’s Great Triangle and the Shape of Space:
[103] Beauty is the First Test:

June 2014

[102] Balancing a Pencil: .
[101] When did Hammurabi reign?
[100] Biscuits, Books, Coins and Cards: Massive Hangovers:
[99] Sunflowers and Fibonacci: Models of Efficiency: Patterns in nature.

May 2014
[98] The High-Power Hypar:
[97] The Chaos Game: .
[96] The Future of Society: Prosperity or Collapse?
[95] Predator-Prey Models:
[94] The Faraday of Statistics:
April 2014
[93] Breaking Weather Records:
[92] Clothoids Drive Us Round the Bend:
[91] Rollercoaster Loops:
[90] The Predictive Power of Maths: .

March 2014

[89] Solar System Perturbations: .
[88] The Unity of Mathematics: Tendency to fragment is offset by dramatic synthesis.
[87] The Langlands Program: .
[86] Simulating the Future Climate:

February 2014

[85] The Prime Number Theorem:
[84] Euclid in Technicolor: Oliver Byrne’s amazing edition of Euclid.
[83] Speed Cubing & Group Theory: Cubophiles can solve the problem in 5 seconds.
[82] French Curves and Bézier Splines

January 2014

[81] Bézout’s Theorem:
[80] Pythagorean triples:
[79] Robots & Biology: The interplay between mechanics and biological systems.
[78] White Holes in the Kitchen Sink:
[77] Interesting Bores:

December 2013

[76] Experiment and Proof:
[75] Santa’s Fractal Journey:
[74] Ireland’s Fractal Coastline:
[73] Population Projections:

November 2013

[72] A Simple Growth Function:
[71] The Antikythera Mechanism:
[70] The Watermelon Puzzle:
[69] Euler’s Gem: 

October 2013

[68] Hyperbolic Triangles and the Gauss-Bonnet Theorem:
[67] Poincare’s Half-plane Model (bis):
[66] Geometry in and out of this World:
[65] Poincaré’s Half-plane Model:
[64] The Simpler the Better:

September 2013

[63] A Mathematical Dynasty:
[62] Sonya Kovalevskaya:
[61] New Estimate of the Speed of Light:
[60] Irish Maths Week 2013:

August 2013

[59] A Hole through the Earth: Falling to the antipodes
[58] Ternary Variations: Cantor’s surprising ternary set.
[57] Travelling under Pressure: The Atmospheric Railway
[56] The remarkable BBP Formula: Arbitrary (hex) digits of pi
[55] Admirably Appropriate: Symbiosis between pure and applied mathematics

July 2013
[54] Paddling Uphill: Apparent uphill flow of River Shannon.
[53] Matholympic Heroes: The IMO in Santa Marta, Colombia.
[52] Hailstone Numbers: A challenging problem in number theory.
[51] The School of Athens: Projective geometry and the mathematics of perspective.

June 2013

[50] Senior Wranglers: Wranglers and the Mathematical Tripos.
[49] Normal Numbers: Surprising properties of Champernowne’s Number.
[48] Joyce’s Number: Maximum number using three 9s.
[47] Prime Secrets: Two exciting results in prime number theory.

May 2013

[46] Gauss’s Oversight: Gauss misses a crucial connection.
[45] The Sholders of Giants: The mathematician John Wallis.
[44] Kelvin Wakes: Beautiful ship-wave patterns.
[43] Loaves & Fishes: The Banach-Tarski Theorem.
[42] Monster Symmetry: The monster group and symmetry in physics.

April 2013
[41] Spots & Stripes: Reaction-diffusion processes and pattern generation.
[4-] The Dozenal System: Base-twelve arithmetic.
[39] Pythagoras goes Global: Pythagoras’ Theorem on the sphere.
[38] Bayes Rules OK: Many implications of Bayes’ Theorem.

March 2013
[37] Peaks, Pits & Passes: Some properties of maps and charts.
[36] The Pitch-drop Experiment: A long-running physics experiment.
[35] Happy Pi-Day: 3/14, a cause for celebration.
[34] CAT Scans: Medical imaging and the Radon transform.
[33] More Equal than Others: Robert Recorde and the “=” sign.

February 2013
[32] The Swingin’ Spring: Complex dynamics of a simple mechanical system.
[31] SVD: The invaluable Singular Value Decomposition.
[30] Computer Maths: Will computers ever be able to do mathematical research?

January 2013
[29] Chess Harmony: Some properties of the harmonic series.
[28] The Lambert W-function: An interesting special function.
[27] Topology Underground: The geometry and topology of subway systems.
[26] The Power Tower: Surprising convergence of iterated exponents.
[25] Archimedes Uncovered: The Archimedes Palimpsest.

December 2012
[24] Pons Asinorum: A startling geometric proof.
[23] Santa’s Challenge: Santa Claus and the travelling salesman problem.
[22] Sharing a Pint: An amusing puzzle for the pub.
[21] Ramanujan’s Lost Notebook: Ramanujan’s papers found in the Wren Library.

November 2012
[20] Taxi-cab Geometry: Where circles are square and pi equals 4.
[19] Surreal Numbers: Conway’s ingenious transfinite numbers.
[18] Where in the World: GPS and relativity.
[17] Shackleton’s Spectacular: An amazing feat of navigation.
[16] A Mersennery Quest: GIMPS and the search for Mersenne primes.

October 2012
[15] The Popcorn Function: A function with extraordinary continuity properties.
[14] Carving up the Globe: Many ways to dissect the sphere.
[13] The Falling Slinky: The bottom stays still!
[12] Contagion: Modelling infectious diseases.

September 2012
[11] The End of Small-pox: Daniel Bernoulli and innoculation.
[10] The Kahn Academy: A revolution on maths education.
[9] The Beautiful Game: Golden section nowhere to be seen.
[8] Packing & Stacking: From Kepler to Hales.
[7] No Maths Involved: Aspects of Sudoku.
August 2012
[6] Sproutology: Another clever invention of John Conway.
[5] Analemmatic Sundials: You are the gnomon (pointer).
[4] Napier’s Nifty Rules: Spherical trigonometry made simple.
[3] PageRank: How Google finds things fast.

July 2012
[2] The Two Cultures: Beethoven and Gauss.
[1] That’s Maths: Articles in The Irish Times.

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