1,112 reputation
729
bio website math.stackexchange.com/users/…
location Antarctica
age 79
visits member for 2 years
seen Oct 16 at 9:51

Self-learning mathematics. Many thanks to those who make time to help others on the site.


Jan
5
comment Proof involving Stirling numbers of the second kind
@BrianM.Scott Yeah, I'm looking at it right now and it says, in italics, all positive integers x.
Jan
5
asked Proof involving Stirling numbers of the second kind
Jan
3
comment prove that $\text{rank}(AB)\ge\text{rank}(A)+\text{rank}(B)-n.$
Have you tried working out an example? Try a few by hand and see if you can generalize it. Or you can try showing it by contradiction; though I always feel direct proofs are much more clear.
Jan
2
accepted How to simplify this equality (factorials)?
Jan
2
asked How to simplify this equality (factorials)?
Dec
28
accepted Pigeon-hole Principle: Does this proof have a typo?
Dec
28
accepted If an integer is divisible by 8 and 15, then the integer also must be divisible by which of the following?
Dec
28
accepted How is this a property of Pascal's triangle?
Dec
26
awarded  Analytical
Dec
26
asked How is this a property of Pascal's triangle?
Dec
20
comment If an integer is divisible by 8 and 15, then the integer also must be divisible by which of the following?
Ah! I figured it out just now. Thank you
Dec
20
comment If an integer is divisible by 8 and 15, then the integer also must be divisible by which of the following?
What else does it imply? (I actually thought about it, but I'm quite hesitant to state what I think).
Dec
20
asked If an integer is divisible by 8 and 15, then the integer also must be divisible by which of the following?
Dec
20
awarded  Supporter
Dec
20
comment Pigeon-hole Principle: Does this proof have a typo?
Ah yes, that's what I figured. I was thinking that if it were less than, say a radius of 0.01, then you could definitely arrange the dots so that the circumcircles don't contain them.
Dec
19
asked Pigeon-hole Principle: Does this proof have a typo?
Dec
11
awarded  Editor
Dec
11
awarded  Scholar
Dec
11
accepted I can't figure out this combinatorics problem… Or at least why my solution doesn't work.
Dec
11
revised I can't figure out this combinatorics problem… Or at least why my solution doesn't work.
added 62 characters in body