Chronology of Updates


I have placed chronology of updates for 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 and 2017 into separate files. Starting with 1997, the most recent entries appear topmost. Besides providing an insight into this site's evolution, chronology of updates may be used for word searches.

July 6 Lorian Saceanu's Inequality for All Triangles
July 5 Probability in Triangle
July 4 Diminishing Hopes II
July 3 An Inequality from a Mongolian Exam
July 1 Probability of Successive Integers
June 30 Dorin Marghidanu's Functional Equation
June 29 Product of Integers that Add Up to 2018
June 28 An Integer Root of a Polynomial with Integer Coefficients
June 27 A Problem form the Short List of the 2018 JBMO
June 25 A Problem of Divisibility by 17 from the 1894 Eotvos Competition
June 23 An Inequality in Triangle for Side Lengths, Cycled in Two Ways
June 21 A Triangle out of Three Broken Sticks
June 19 Probability of Doubles
June 18 A Coin Tossing Surprise I
June 17 Fair Duel
June 15 Is a Sum a Prime Number?
June 15 A Moscow Olympiad Question with Two Inequalities
June 14 Lucky Times at a Moscow Math Olympiad
June 12 Averages of Terms in Increasing Sequence
June 12 An Inequality in Triangle with Radicals, Semiperimeter, Incenter and Inradius
June 11 An Equation in Factorials
June 10 Folding and Cutting a Square
June 6 Getting from A to B via C
June 6 Two Constraints, One Inequality by Qing Song
June 5 Lorian Saceanu's Sides And Angles Inequality
June 4 Probability of No Distinct Positive Roots
June 4 Rolling Defective Die
June 3 Dorin Marghidanu's Inequality with Powers and Reciprocals
June 2 An Inequality for the Tangent to the Incircle
June 1 Two Dice Repetition
May 29 Lucky Contest Winners
May 28 Random Clock Hands
May 27 Randomly Placed Letters in Envelopes
May 26 Leo Giugiuc's Cyclic Inequality in Square Roots
May 25 Probability of Equal Areas on a Chessboard
May 25 Points in a Semicircle
May 24 Point between Two Roads
May 22 How Long Will It Last?
May 21 Leo Giugiuc's Cyclic Inequality with a Constraint
May 18 An Incidental Sum of 24
May 16 Check for Negative Roots
May 16 Mehmet Sahin's Identity in Triangle
May 15 Emptying a Big Number of Boxes
May 14 A True Algebraic-Geometric Inequality
May 14 The Shortest Distance in a Circular Segment
May 14 Lorian Saceanu's Inequality with Many Variables
May 13 Seven Integers That Add Up to 100
May 13 A Cyclic Inequality in Three Variables XXVI
May 12 Counting Coins and Their Values
May 12 An Inequality with Two Variables from Awesome Math
May 11 Fixed Point of a Family of Parabolas
May 10 Expectation of Pairings
May 9 Minimum of Cotangents from Saint Petersburg
May 9 Leo Giugiuc and Vasile Cirtoaje's Cyclic Inequality
May 9 Vasile Cirtoaje's Cyclic Inequality with Three Variables
May 8 Probability of Having 5 in the Numerator
May 7 Find the Maximum and Minimum of a Function
May 6 Waiting for a Train
May 5 Probability of Equilateral Triangle
May 4 Lorian Saceanu's Cyclic Inequalities with Three Variables
May 4 Integer Sequence with Given Statistical Parameters
May 4 Thanos Kalogerakis' Collinearity in Triangle
May 3 Dan Sitaru's Inequality with Radicals and Cosines
May 3 Asymmetric Propeller of Squares II
May 2 An Inequality in Triangle with Radicals, Semiperimeter and Inradius
May 2 Asymmetric Propeller of Squares
May 1 Dan Sitaru's Cyclic Inequality in Three Variables IX
Apr 30 An Identity in Bicentric Isosceles Trapezoid
Apr 26 Random Arithmetic Progressions
Apr 25 Average Number of Runs in a Sequence of Random Numbers
Apr 24 Two Varsity Divisions
Apr 24 Labeling Subsets
Apr 23 Bubbling of Sorts
Apr 21 Equilateral Triangle from Three Centroids
Apr 21 Cutting a Cube into Smaller Ones
Apr 20 The Circle of the Orthocenters
Apr 20 A 2-Variable Optimization From a China Competition
Apr 19 Probability of Majorization II
Apr 19 Inheriting Inequality
Apr 17 Training Bicyclists on a Mountain Road
Apr 17 A Simple Integral of a Peculiar Function
Apr 17 Pythagorean Theorem by Contradiction
Apr 16 A Few Variants of a Popular Inequality And a Generalization
Apr 15 Two Balls of the Same Color
Apr 15 Probability in Scoring
Apr 14 Two Balls Out Of Four
Apr 14 Cyclic Inequality In Three Variables from the 2018 Romanian Olympiad, Grade 9
Apr 13 Cyclic Inequality in Four Variables By D. Sitaru
Apr 13 A Question about the Median
Apr 12 A Fancy Sum from the APMO 2000, Problem 1
Apr 12 Lights on a Christmas Tree
Apr 12 Cyclic Inequality In Three Variables From Vietnam by Rearrangement
Apr 11 A Quick Proof of cos(pi/7)cos(2.pi/7)cos(3.pi/7)=1/8
Apr 11 A Search for heads and Its Consequences - After Miller And Sanjurjo
Apr 11 Cyclic Inequality in Four Variables
Apr 11 An Inequality in a Convex Quadrilateral
Apr 10 A Simple Inequality with Many Variables
Apr 10 Cyclic Inequality In Three Variables From Kvant
Apr 9 Problem 8 from the Spring 2018 Mathcounts
Apr 9 Two Colors - Three Points - Any Triangle
Apr 8 Problem 25 from the Spring 2018 Mathcounts
Apr 7 A Problem of Three Liars
Apr 7 A Problem of Two Liars
Apr 7 Looking for the Prime Decomposition
Apr 6 Distributing Balls of Two Colors in Two Bags
Apr 5 An Inequality in a Nonobtuse Triangle
Apr 5 A Broken Line in 3D
Apr 5 Artificially Unintelligent
Apr 4 Galton's Paradox
Apr 4 An Inequality with Cubic Roots
Apr 3 Factorial Divisibility
Apr 2 Playing with Balls of Two Colors
Apr 2 An Inequality with Central Binomials
Apr 2 An Appearance of a 30-60-90 Triangle
Apr 1 A Remote Decimal Digit
Mar 29 Alexandru Lupas' Property of the Incenter
Mar 29 Taking Turns to Toss a Die
Mar 28 A Missing Digit
Mar 27 Two 6s in a Row
Mar 27 Second Pair of Twin Inequalities: Twin 2
Mar 27 Second Pair of Twin Inequalities: Twin 1
Mar 26 Planting Trees in a Row
Mar 25 Probability of Average
Mar 24 Equilateral Triangle In a Pretty Diagram
Mar 24 Yet Another Simple Integral
Mar 24 Red Faces of a Cube
Mar 23 Butterfly in Complex Numbers
Mar 23 Coloring Squares, Adding up Numbers
Mar 23 In Praise of Odds
Mar 22 Taking Chances with Your Medicine
Mar 21 Dan Sitaru's Cyclic Inequality In Three Variables with Constraints V
Mar 21 Probability of the Second Marble
Mar 20 On Gauss' Shoulders
Mar 19 A Little More of Algebra for an Inequality, A Little Less of Calculus for a Generalization
Mar 19 Right Strategy for a Weaker Player
Mar 18 Planar Sets with Integer Distances between Points
Mar 18 Random Numbers And Obtuse Triangle
Mar 17 A Little of Algebra for an Inequality, A Little of Calculus for a Generalization
Mar 16 Probability of First Digit in Product
Mar 15 Walking Randomly - How Far?
Mar 14 Trigonometric Identity for the Pi Day
Mar 13 A Property of Nagel Cevians
Mar 12 Gambling in a Company
Mar 10 Losing Socks Over a Year
Mar 9 Probability of First Digits in a Sequence of Powers
Mar 7 Probability of No Two-Tail Runs
Mar 6 Crossing Bridge in Crowds
Mar 6 Diagonals in a Polygon Parallel to Sides
Mar 5 An Inequality with Five Variables, Only Three Cyclic
Mar 4 Two Coins: One Fair, one Biased
Mar 4 Probability in the World Series
Mar 3 Illustrated Sum of Cubes - All in a Plane
Mar 3 Golden Ratio in Yin-Yang
Mar 3 An Estimate for the Roots of Quadratic Equation
Mar 2 A Cyclic Inequality by Seyran Ibrahimov
Mar 2 An Exercise in Complex Numbers: Problem 4217 from Crux
Mar 1 Clumps on a One Lane Road
Feb 28 A Straightedge Construction of the Midpoint of a Chord Common to Two Circles
Feb 27 Golden Ratio in Isosceles Triangle II
Feb 26 Hung Nguyen Viet's Inequality with a Constraint
Feb 26 Expected Number of Happy Passengers
Feb 24 A Curious Property of Numbers 3 and 5
Feb 24 A Three Group Split
Feb 23 Probability in Dart Throwing
Feb 23 Snake Permutations And Their Number
Feb 23 An Inequality in Triangle form the 1996 APMO
Feb 22 Kunihiko Chikaya's Inequality with a Constraint
Feb 22 Expectation of the Largest Number
Feb 21 Cute Exercise by Dorin Marghidanu
Feb 21 Arithmetic of Pie Sharing
Feb 21 Dan Sitaru's Inequality with a Double Integral
Feb 20 Circle Center by Paperfolding
Feb 20 Waiting for All Six Outcomes
Feb 19 Golden Ratio in Circles
Feb 19 Uniqueness of Number 5
Feb 18 Luca Moroni's Problem In Equilateral Triangle
Feb 18 A Triangle in a Rhombus with a 60 Degrees Angle
Feb 17 Acting As a Team I
Feb 16 Two in a Row
Feb 15 Golden Ratio in Isosceles Triangle
Feb 15 A Property of Angle Bisectors
Feb 15 Probability of a Random Inequality
Feb 14 Probability of a Meet in an Elimination Tournament
Feb 14 Golden Ratio in Two Squares, Or, Perhaps in Three
Feb 14 Thanos Kalogerakis's Problem in Circle and Square
Feb 13 Playing with Integers and Limits
Feb 13 Golden Ratio in Equilateral Triangle on the Shoulders of George Odom
Feb 13 A Modified Sangaku
Feb 11 Converting Temperature From $C^{\circ}$ to $F^{\circ}$
Feb 11 A Problem in a Configuration of Three Squares
Feb 10 Golden Ratio in Square
Feb 9 Triangle on a Rectangular Hyperbola
Feb 9 Euler Line Through a Vertex
Feb 9 Ji Chen's Inequality
Feb 9 Functional Inequality from Vietnam
Feb 8 Matching Socks in Dark Room
Feb 8 Guessing Hat Numbers
Feb 6 Inequality in Convex Quadrilateral
Feb 5 Solving a Peculiar Third Degree Equation
Feb 5 Stars in Array
Feb 3 Equal And Perpendicular Segments in a Square
Feb 1 Expectation of Interval Length on Circle
Feb 1 Waiting to Exceed 1
Feb 1 An Angle Inequality in Triangle with Perpendicular Medians
Feb 1 The Triangle of the Medians
Jan 30 Waiting for a Larger Number
Jan 30 Elegance in Integers by Dorin Marghidanu
Jan 30 Hadamard's Determinant Inequalities and Applications II
Jan 30 A Trigonometric Inequality with Ordered Triple of Variables
Jan 29 An Inequality with Two Triples of Variables II
Jan 25 Two Equilateral Triangles on Sides of a Square
Jan 25 Hadamard's Determinant Inequalities and Applications I
Jan 25 Random Sum
Jan 24 Number of Wire Loops
Jan 24 Probability of Random Lines Crossing
Jan 24 Shelving an Encyclopaedia
Jan 23 Tony Foster's Integer Powers in Pascal's Triangle
Jan 22 A Triangle Problem from Caucasus
Jan 22 The Most Likely Position
Jan 20 Volume Inequality in Tetrahedron
Jan 20 An Isoperimetric Problem in Quadrilateral
Jan 18 Dan Sitaru's Cyclic Inequality in Three Variables VIII
Jan 17 The Expected Number of Fixed Points
Jan 16 Choosing the Largest Random Number
Jan 16 Golden Ratio in Square And Circles
Jan 15 Pythagorean Theorem by Stretching
Jan 15 Quadrilateral Inscribed into Parallelogram
Jan 14 Dan Sitaru's Cyclic Inequality in Three Variables VII
Jan 14 Probability of an Odd Number of Sixes
Jan 14 To Bet Or Not To Bet
Jan 14 Simple Nameless Inequality
Jan 14 Dorin Marghidanu's Sums and Products
Jan 13 Three Complex Numbers Satisfy Fermat's Identity For Prime Powers
Jan 13 Dropping Numbers into a 3x3 Square
Jan 12 Sam Walters' Four Questions
Jan 12 Piecewise Carpets in Parallelogram
Jan 11 Why Can't They Be All Different?
Jan 11 6th European Mathematical Cup (2017), Junior Problem 4
Jan 8 Metamorphosis of a Quadratic Function
Jan 7 Flat Probabilities on a Sphere
Jan 6 A Welcome Problem for the Year 2018
Jan 6 A Farewell Problem for the Year 2017
Jan 6 An Inequality Involving Arithmetic And Geometric Means
Jan 5 The Marriage Problem
Jan 4 An Extension of a Sangaku with Touching Circles
Jan 4 The Coffee Shop Game
Jan 2 An Inequality with Two Triples of Variables
Jan 1 Flat Probabilities on a Sphere

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Copyright © 1996-2018 Alexander Bogomolny