# New in *MathWorld* -- February
2005

### Monday February 28, 2005

- Mersenne Number (modified)
- Moduli Space (modified)
- Nonparametric Estimation (modified)

### Sunday February 27, 2005

- Erfc (modified)
- Golomb Ruler (modified)
- Ham Sandwich Theorem (modified)
- Nine-Point Center (modified)
- Orthocenter (modified)
- Snub Cube (modified)
- Triangle Centroid (modified)
- Tribonacci Constant
- Tribonacci Number (modified)
- Twistor Correspondence (modified)
- van der Pol Equation (modified)

### Saturday February 26, 2005

- 42 (modified)
- Central Trinomial Coefficient (modified)
- Integer Sequence Primes (modified)
- Mersenne Prime (modified)
- Primality Test (modified)
- Prime Number (modified)
- Tetrahedral Number (modified)
- Titanic Prime (modified)
- Trinomial Coefficient (modified)

### Friday February 25, 2005

- Erfc (modified)
- Hypercube Line Picking (modified)
- Reflection Triangle (modified)
- Simulated Annealing (modified)

### Thursday February 24, 2005

- Central Binomial Coefficient (modified)
- Central Trinomial Coefficient (modified)
- Erf (modified)
- Prime Arithmetic Progression (modified)
- Ulam Sequence (modified)

### Wednesday February 23, 2005

- Erf (modified)
- Heptic Surface (modified)
- Hypercube Line Picking (modified)
- Integer Value
- Labs Septic
- Ordinary Double Point (modified)
- Rational Number (modified)
- Septic Surface

### Tuesday February 22, 2005

- Congruence (modified)
- Harmonic Series (modified)
- Mod (modified)
- Prime Number (modified)
- Quotient (modified)
- Rational Number (modified)

### Monday February 21, 2005

- i (modified)

### Sunday February 20, 2005

- Icosahedron (modified)
- Ptolemy Inequality (modified)
- Strong Law of Small Numbers (modified)
- Triacontahedron (modified)
- Tweedie's Theorem

### Saturday February 19, 2005

- Pompeiu's Theorem
- Trinomial Triangle (modified)

### Friday February 18, 2005

- 42 (modified)
- Algebraic Topology (modified)
- Combinatorial Topology (modified)
- Echelon Form (modified)
- Goldbach Conjecture (modified)
- i (modified)
- Integer Sequence Primes (modified)
- Mersenne Number (modified)
- Mersenne Prime (modified)
- Riemann Zeta Function Zeros (modified)
- Topology (modified)
- Trinomial Coefficient (modified)

### Thursday February 17, 2005

- Aleph-0 (modified)
- Aleph-Null
- Banach Space (modified)
- Contour Integral (modified)
- Cosecant (modified)
- Cotangent (modified)
- Decahedron (modified)
- Dihedral Group (modified)
- Echelon Form (modified)
- Eigenfunction (modified)
- Group Upper Central Series
- McCarthy 91-Function (modified)
- Nilpotent Group (modified)
- Pole (modified)
- Real Line (modified)
- Ring (modified)
- Secant (modified)
- Sphere (modified)
- Spherical Harmonic (modified)
- Topological Space (modified)
- Topology (modified)
- Unit Interval
- Zorn's Lemma (modified)

### Wednesday February 16, 2005

- Armstrong Number (modified)
- Bernoulli Polynomial (modified)
- Darboux Cubic (modified)
- Narcissistic Number (modified)
- Oblate Spheroid (modified)
- Spheroid (modified)
- Wilson's Theorem (modified)

### Tuesday February 15, 2005

- Apex
- Decahedron (modified)
- Dodecahedron (modified)
- Echelon Form
- Ellipsoid (modified)
- Enneahedron (modified)
- Icositetrahedron (modified)
- Math (modified)
- Maths (modified)
- Nonahedron (modified)
- Octahedron (modified)
- Sum of Prime Factors (modified)
- Tetradecahedron (modified)

### Monday February 14, 2005

- Hofstadter Ellipse (modified)
- Simple Group (modified)

### Saturday February 12, 2005

- Integer Sequence Primes (modified)

### Friday February 11, 2005

- Abelian Group (modified)
- Abelian Semigroup
- Consecutive Number Sequences (modified)
- Finitely Presented Group
- First Brocard Cevian Triangle
- First Yff Triangle (modified)
- Labyrinth
- Maze (modified)
- Second Brocard Cevian Triangle
- Symmedial Triangle (modified)
- van Aubel's Theorem (modified)
- Voter Model

### Thursday February 10, 2005

### Wednesday February 9, 2005

- Cross Product (modified)
- Lemoine Hexagon (modified)
- Remez Algorithm (modified)
- Remez Exchange Algorithm

### Tuesday February 8, 2005

- Aubel's Theorem (modified)
- Central Line (modified)
- Cube Division by Planes (modified)
- Hexyl Triangle (modified)
- Lucas Central Triangle (modified)
- MacBeath Circle (modified)
- Matchstick Graph (modified)
- Orthic Inconic (modified)
- Principle of Uniform Boundedness (modified)
- Rabin's Compression Theorem (modified)
- Reflection Triangle (modified)
- Riemann Zeta Function (modified)
- Square Division by Lines (modified)
- Unicursal Circuit (modified)
- Uniform Boundedness Principle (modified)
- van Aubel Line
- van Aubel's Theorem (modified)

### Monday February 7, 2005

- Euler Infinity Point (modified)
- Factorial Products (modified)
- Math
- Mathematics (modified)
- Maths
- Napoleon-Feuerbach Cubic
- Nine-Point Circle (modified)
- Oloid
- Pivotal Isogonal Cubic (modified)
- Reflection Circle (modified)
- Reflection Triangle (modified)
- Son
- Steiner's Problem (modified)

### Sunday February 6, 2005

- Antiorthic Axis (modified)
- Brocard Axis (modified)
- Cube Line Picking (modified)
- Cube Triangle Picking (modified)
- Disk Triangle Picking (modified)
- Euler Line (modified)
- Fermat Axis (modified)
- Gergonne Line (modified)
- Hexagon Triangle Picking (modified)
- Line at Infinity (modified)
- Nagel Line (modified)
- Pentagon Triangle Picking
- Soddy Line (modified)
- Tetrahedron Line Picking (modified)
- Tetrahedron Tetrahedron Picking (modified)
- Tetrahedron Triangle Picking (modified)
- Triangle Line Picking (modified)
- Triangle Triangle Picking (modified)
- Yiu Circles (modified)

### Saturday February 5, 2005

- Almost Integer (modified)

### Friday February 4, 2005

- Geometric Probability (modified)
- Iff (modified)
- Tetrahedron Line Picking
- Tetrahedron Triangle Picking

### Thursday February 3, 2005

- Barker Code (modified)
- Droz-Farny Theorem (modified)
- Euler Number (modified)
- Isogonal Transform
- Isotomic Conjugate (modified)
- Isotomic Transform
- Isotomic Transversal (modified)
- Pisot Number (modified)
- Pisot-Vijayaraghavan Constant (modified)
- Polynomial Factor Theorem
- Reflection Circle (modified)
- Square Triangle Picking (modified)

### Wednesday February 2, 2005

- BellB
- BellY
- Digitaddition (modified)
- Full Reptend Prime (modified)
- HankelH1
- HankelH2
- Integer Sequence Primes (modified)
- KelvinBei
- KelvinBer
- KelvinKei
- KelvinKer
- ParabolicCylinderD
- SphericalBesselJ
- WhittakerM
- WhittakerW

### Tuesday February 1, 2005

- Folding (modified)
- Reflection Circle (modified)
- Reflection Triangle (modified)

[ 2024 ▪ 2023 ▪ 2022 ▪ 2021 ▪ 2020 ▪ 2019 ▪ 2018 ▪ 2017 ▪ 2016 ▪ 2015 ▪ 2014 ▪ 2013 ▪ 2012 ▪ 2011 ▪ 2010 ▪ 2009 ▪ 2008 ▪ 2007 ▪ 2006 ▪ 2005 ▪ 2004 ▪ 2003 ▪ 2002 ▪ 2001 ▪ 2000 ▪ 1999 ]