MJD

Philadelphia, USA

http://blog.plover.com/

I am an amateur mathematician and a professional computer programmer.

I have a blog that often carries articles about mathematics.

I wrote the book Higher-Order Perl.

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Proof that ${\left(\pi^\pi\right)}^{\pi^\pi}$ (and now $\pi^{\left(\pi^{\pi^\pi}\right)}$) is a noninteger.

number-theory numerical-methods arithmetic pi asked May 13 '13 at 19:47

math.stackexchange.com

130 votes

Why does mathematical convention deal so ineptly with multisets?

notation terminology math-history multisets asked May 31 '12 at 21:20

math.stackexchange.com

117 votes

Why are the solutions of polynomial equations so unconstrained over the quaternions?

abstract-algebra polynomials roots quaternions division-algebras asked Mar 21 '12 at 14:42

math.stackexchange.com

84 votes

Is the notorious $n^2 + n + 41$ prime generator the last of its type?

number-theory asked Jan 28 '13 at 23:08

math.stackexchange.com

60 votes

How can I show that $\sqrt{1+\sqrt{2+\sqrt{3+\sqrt\ldots}}}$ exists?

sequences-and-series limits nested-radicals asked Jul 6 '13 at 3:19

math.stackexchange.com

46 votes

Why does the Hilbert curve fill the whole square?

real-analysis reference-request examples-counterexamples fractals asked May 6 '12 at 22:19

math.stackexchange.com

45 votes

Is there a rational number between any two irrationals?

real-analysis irrational-numbers rational-numbers asked Jun 16 '13 at 2:17

math.stackexchange.com

41 votes

Who discovered this number-guessing paradox?

probability reference-request math-history paradoxes asked Mar 12 '14 at 21:06

math.stackexchange.com

41 votes

What is the Coxeter diagram for?

geometry reference-request notation polyhedra coxeter-groups asked Apr 1 '14 at 20:48

math.stackexchange.com

33 votes

What is so mysterious about Archimedes' approximation of $\sqrt 3$?

mathematics computation archimedes asked Jan 1 '15 at 21:45

hsm.stackexchange.com

Top Answers

578

In simple English, what does it mean to be transcendental?

math.stackexchange.com

209

Find a prime factor of $7999973$ without a calculator

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208

Examples of bijective map from $\mathbb{R}^3\rightarrow \mathbb{R}$

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171

'Obvious' theorems that are actually false

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157

'Obvious' theorems that are actually false

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145

In the history of mathematics, has there ever been a mistake?

math.stackexchange.com

141

Examples of mathematical discoveries which were kept as a secret

math.stackexchange.com

137

What was the first bit of mathematics that made you realize that math is beautiful? (For children's book)

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124

On “familiarity” (or How to avoid “going down the Math Rabbit Hole”?)

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118

'Obvious' theorems that are actually false

math.stackexchange.com

112

Nice examples of groups which are not obviously groups

math.stackexchange.com

109

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math.stackexchange.com

'Obvious' theorems that are actually false

math.stackexchange.com

Is “$a + 0i$” in every way equal to just “$a$”?

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Mathematicians ahead of their time?

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Are there periodic functions without a smallest period?

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Why not to extend the set of natural numbers to make it closed under division by zero?

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How were 'old-school' mathematics graphics created?

math.stackexchange.com

How can a mug and a torus be equivalent if the mug is chiral?

math.stackexchange.com

Help: rules of a game whose details I don't remember!

math.stackexchange.com

What is a simple example of an unprovable statement?

math.stackexchange.com

Why is ${x^{\frac{1}{2}}}$ the same as $\sqrt x $?

math.stackexchange.com

Are there any examples of non-computable real numbers?

math.stackexchange.com

Must a monotone function have a monotone derivative?

math.stackexchange.com

'Obvious' theorems that are actually false

math.stackexchange.com

Why is $\sqrt{8}/2$ equal to $\sqrt{2}$?

math.stackexchange.com

What are well-defined functions?

math.stackexchange.com

Why is union sign not allowed to denote intervals of function increasing?

math.stackexchange.com

Best Book For Differential Equations?

math.stackexchange.com

Can you construct a field with 6 elements?

math.stackexchange.com

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MJD

Proof that ${\left(\pi^\pi\right)}^{\pi^\pi}$ (and now $\pi^{\left(\pi^{\pi^\pi}\right)}$) is a noninteger.

Why does mathematical convention deal so ineptly with multisets?

Why are the solutions of polynomial equations so unconstrained over the quaternions?

Is the notorious $n^2 + n + 41$ prime generator the last of its type?

How can I show that $\sqrt{1+\sqrt{2+\sqrt{3+\sqrt\ldots}}}$ exists?

Why does the Hilbert curve fill the whole square?

Is there a rational number between any two irrationals?

Who discovered this number-guessing paradox?

What is the Coxeter diagram for?

What is so mysterious about Archimedes' approximation of $\sqrt 3$?