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visits member for 4 years
seen 7 hours ago

Don't have much time these days...


Sep
8
answered Big O boundary condition truth value
Sep
7
answered Is this a known algebraic identity?
Sep
7
comment Can we slice an object into two pieces similar to the original?
A couple of questions. 1) What exactly does split mean? 2) Why is this tagged topology?
Sep
7
revised Is there an elementary proof that $\sum \limits_{k=1}^n \frac1k$ is never an integer?
made the formulae look bigger, using \displaystyle
Sep
7
revised How to expand and simplify $(p^y * (pq)^o) / (p^{(2y+o)} * q^{(o-2)})$?
latex and retagged.
Sep
7
comment A zero sum subset of a sum-full set
@Robby: Thanks to Robby too, I see the deleted answer.
Sep
7
comment A zero sum subset of a sum-full set
@Tony: Thanks for the link!
Sep
7
answered Beautiful identity: $\sum_{k=m}^n (-1)^{k-m} \binom{k}{m} \binom{n}{k} = \delta_{mn}$
Sep
6
comment Find polynomials such that $(x-16)p(2x)=16(x-1)p(x)$
@bill: Thanks. +1.
Sep
6
accepted Irrational painting device
Sep
6
comment Find polynomials such that $(x-16)p(2x)=16(x-1)p(x)$
btw, Thank you for taking the time to write this out! Sorry for the possibly basic question.
Sep
6
awarded  Enlightened
Sep
6
comment Find polynomials such that $(x-16)p(2x)=16(x-1)p(x)$
How do you get $(S-1)f = (S^4-1)g$? What does $S-1$ even mean?
Sep
6
awarded  Nice Answer
Sep
6
awarded  Nice Question
Sep
6
revised finding seven disjoint seven element subsets of {1,2, …, 49} with same sum
edited title, formatting.
Sep
6
answered finding seven disjoint seven element subsets of {1,2, …, 49} with same sum
Sep
6
comment $5^n+n$ is never prime?
Nice! Please do update us if you do let Primo finish.
Sep
6
comment Cutting sticks puzzle
Yes, this is incorrect. You might glue it, but you have not ensured that the resulting split happens at the spot where you glued.
Sep
6
comment If $(a^{n}+n ) \mid (b^{n}+n)$ for all $n$, then $ a=b$
@Jason: math.stackexchange.com/questions/4125/5nn-is-never-prime