4,096 reputation
2248
bio website quora.com/Alon-Amit
location Los Altos, CA
age 46
visits member for 5 years, 11 months
seen 14 hours ago

Dabbler in things.


Jan
11
answered About an exercise in Serre's “Trees”
Jan
4
comment Is “second-countable implies separable” equivalent to the Axiom of countable Choice?
Surely this requires only the axiom of countable choice?
Dec
22
awarded  Nice Answer
Dec
8
comment How many finite simple groups of order $p+1$?
n!/2-1 is prime for n=5, 6, 9, 31, 41, 373 ... (sequence A082671 on the OEIS). Is it known if this sequence is finite?
Dec
5
awarded  Nice Answer
Nov
30
comment Ingenuity in mathematics
To complete the triviality of the situation, after your audience proposes a bunch of complex strategies, propose an alternative game whereby after "STOP" it's the last card in the deck that gets turned over. Everyone sees that this game is strategy-indifferent, and then you deliver the coup de grace... I've used this several times in math circles. Gets them every time.
Nov
13
awarded  Popular Question
Nov
10
comment Proofs without words
Done! Thanks for the comment.
Nov
10
revised Proofs without words
Replaced image url; added 348 characters in body
Nov
2
awarded  Nice Answer
Nov
2
awarded  Nice Question
Nov
1
answered Most memorable titles
Oct
27
revised P-adic L functions
minor LaTeX fix
Oct
12
comment roots of permutations
True. My answer attempts to generalize further into equations in several variables.
Oct
12
answered roots of permutations
Sep
30
awarded  Yearling
Sep
19
comment 4-colorable graphs
It's even falser :-) In fact, there are graphs with high girth and high chromatic number. A graph with high girth looks like a tree around any vertex, so it avoids much more than just triangles. Proving that such graphs exist is perhaps even simpler than the explicit construction by Mycielski; it's basically a counting argument.
Sep
11
awarded  Nice Answer
Sep
10
answered What is the easiest randomized algorithm to motivate to the layperson?
Aug
28
revised Does the “continuous locus” of a function have any nice properties?
added 39 characters in body