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visits member for 2 years, 1 month
seen 2 hours ago

Apr
19
asked Why can't we have an $y$ such that $xy\equiv 1\; (mod\; n)$ when $n$ is not prime?
Apr
19
awarded  Good Question
Apr
14
comment Show that if $a,k\in \mathbb{Z}$ with $0\leq k \leq a$, then $\binom ak=\frac{a!}{k!(a-k)!}=\binom {a}{a-k}$.
Excuse me, It's not really clear why I should do that.
Apr
14
asked Show that if $a,k\in \mathbb{Z}$ with $0\leq k \leq a$, then $\binom ak=\frac{a!}{k!(a-k)!}=\binom {a}{a-k}$.
Apr
14
comment Which triangular numbers are also squares?
What I still don't understand is why that is the condition.
Apr
14
comment Which triangular numbers are also squares?
@AndréNicolas Yes. But does this applies with generality?
Apr
13
comment Which triangular numbers are also squares?
@AndréNicolas Is there a master secret to avoid fractions? I've escaped school, then I don't remember most basic stuff such as this (Presuming it is basic).
Apr
13
comment Which triangular numbers are also squares?
@AndréNicolas I've done the following: $n^2+n+\frac{1}{4}=m^2+\frac{1}{4}$.
Apr
13
asked Which triangular numbers are also squares?
Apr
13
revised Spelling has deteriorated by the year of 2075, how many spellings are possible?
added 15 characters in body
Apr
13
comment Spelling has deteriorated by the year of 2075, how many spellings are possible?
@OlivierBégassat I was thinking about it. Now that you gave the answer, I feel rleiifed. Thanks.
Apr
12
awarded  Nice Question
Apr
12
asked Is there a simple algorithm for exponentiating large numbers to large powers?
Apr
12
revised Does writing a bachelor thesis make sense?
added 2 characters in body
Apr
12
answered Does writing a bachelor thesis make sense?
Apr
12
comment Are there surfaces with more than two sides?
@AlexBecker You can point me to it anyway. I'm studying on a math major, someday I'll understand it.
Apr
12
asked Are there surfaces with more than two sides?
Apr
11
accepted Why $¬¬\bot \not\in PROP$?
Apr
10
comment Why $¬¬\bot \not\in PROP$?
Yes. Thanks guys!
Apr
10
comment Why $¬¬\bot \not\in PROP$?
@AndreasBlass Why each $¬$ needs a pair or parentheses?