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seen Aug 27 at 11:16

Aug
25
comment Injective subset function
You are right that it still works for infinite $X$ if $F(x)$ is always finite. But of course it's trivially false as stated, with no finiteness assumption. I wonder if the OP knows that and just forgot to mention finiteness, or if he really wanted it to be true with no restrictions?
Aug
17
comment Has by well-foundedness every non-empty class an $R$-minimal element? Also if axiom REG is not assumed?
This must be a dumb question, but can you prove (without regularity) that a proper class must have an infinite subset? If $C$ were a proper class with no infinite subsets, then the class of all (finite) subsets of $C$ would be well-founded under reverse inclusion, but would have no "minimal" element.
Aug
15
comment A Banach-Tarski game
Don't you want to say that $bigcup Z_{0,i}$ and $\bigcup Z_{1,i}$ are disjoint unions?
Aug
6
comment Statements reliant on conjectures
Why didn't the axiom of constructibility make your list?
Aug
6
comment Statements reliant on conjectures
Does the simple negation of the continuum hypothesis really have a lot of interesting consequences?
Aug
3
comment Is there a structure theorem or group law for finite groups generated by two elements?
According to Theorem 2.1 of F. Levin, Factor Groups of the Modular Group, J. London Math. Soc 43 (1968), 195-203, every countable group is embeddable in a $2$-generator group with generators of prescribed orders $p\ge3$ and $q\ge2.$
Jun
17
awarded  Enlightened
Jun
14
comment Collection of graduate research projects in Real Analysis
Picking a research problem from the list of answers you're going to get seems kind of risky. How many other graduate students are going to look at this list and pick the same problem you did?
Jun
13
awarded  Nice Answer
Jun
13
revised Avoiding countable subgroups of general uncountable groups
added 1 character in body
Jun
12
awarded  Quorum
Jun
12
revised Avoiding countable subgroups of general uncountable groups
added 57 characters in body
Jun
12
revised Avoiding countable subgroups of general uncountable groups
added 16 characters in body
Jun
12
revised Avoiding countable subgroups of general uncountable groups
deleted 2 characters in body
Jun
12
answered Avoiding countable subgroups of general uncountable groups
Jun
7
revised Not especially famous, long-open problems which higher mathematics beginners can understand
added 299 characters in body
Jun
7
comment Not especially famous, long-open problems which higher mathematics beginners can understand
@AlirezaAbdollahi I found a reference so I'm going to edit it into my answer.
Jun
7
comment $\kappa$-translatability
Some reason you can't ask Carlson? I hope he's OK.
May
6
awarded  Cleanup
May
6
answered Sums of sets of lower density 0