420 reputation
618
bio website ozemail.com.au/~markhurd
location Cherry Gardens, Australia
age 45
visits member for 4 years
seen 10 mins ago

I have a background in VB and C and an Honours degree in Mathematical Sciences from Adelaide University, majoring in Computer Science.

I have over 15 years VB experience and have dealt with back-end details, including without using databases.


Aug
12
answered Is “$a + 0i$” in every way equal to just “$a$”?
Aug
6
comment Relate $\sum{a_n}$ and $\sum{n a_n}$
I asked because I noticed that $\zeta(3)=\sum{1/n^3}=$Apéry's constant and $\zeta(2)=\sum{1/n^2}=\sum{n/n^3}=\frac{\pi^2}{6}$. Given the answer here I asked another question.
Aug
6
accepted Relate $\sum{a_n}$ and $\sum{n a_n}$
Aug
6
accepted What's $\sum{\frac{x^n}{n^3}}$?
Aug
6
asked What's $\sum{\frac{x^n}{n^3}}$?
Aug
6
asked Relate $\sum{a_n}$ and $\sum{n a_n}$
Jul
11
comment Why isn't the Cantor Set contradictory?
Your last paragraph took a moment: until you realize there's actually an infinite number between in both cases, and still countable or not, respectively.
Jul
11
revised What does a “convention” mean in mathematics?
Promote my comment to be part of the answer, because of changes to the Wikipedia link.
Jun
25
comment How big is infinity?
Yes, except for the mapping s typo.
Jun
21
comment Proof that there are infinitely many primes of the form $4m+3$
To be a valid proof of the requested theorem, the first line should be "Assume there are finitely many primes of the form $4m+3$, and take $p_k$ to be the largest."
Jun
21
revised Proof that there are infinitely many primes of the form $4m+3$
Format proof
Jun
21
suggested suggested edit on Proof that there are infinitely many primes of the form $4m+3$
Jun
21
revised Proof of infinitely many primes, clarification
Format the proof readably
Jun
21
suggested suggested edit on Proof of infinitely many primes, clarification
Jun
17
answered What was the book that opened your mind to the beauty of mathematics?
Jun
12
comment 'Obvious' theorems that are actually false
Have you stated the false "theorem", or is this a true counter-intuitive statement? (Clearly I'm not actually intuiting anything :-) )
Jun
12
comment 'Obvious' theorems that are actually false
@user87690 Accepted, and the fault with my statement is the level sets (which is what your $S_n$ are) of an integral are all infinite, but all infinitesimals.
Jun
11
comment Finding out properties of this ODE system knowing only partial informations about it.
This is probably just my misunderstanding of invariant in context, but does the first bolded phrase mean $P(x,y)=Q(x,y)=0$ when $x^2+y^2=k^2$, $k$ an integer, or just that any point on an integral radius will stay on that integral radius (i.e. $\dot{r}=0$, $r$ an integer)?
Jun
11
comment 'Obvious' theorems that are actually false
@user87690 There are finite integrals $\int_1^\infty y, y>0$ so I'd expect an uncountable number of positive values could still have a finite sum.
Jun
10
comment Prove infinite series
But $y<1$, so $x>1$.