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Dominic van der Zypen's user avatar
Dominic van der Zypen's user avatar
Dominic van der Zypen's user avatar
Dominic van der Zypen
  • Member for 14 years, 4 months
  • Last seen this week
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comment
Maximizing the mutual Hamming distance in $\big[{\cal P}([n])\big]^n$
Thanks @RobPratt! Hypothesis: $M_{2k} = k$ for $k>1$ and $M_{2k+1} = k+1$ for $k>2$?
asked
Maximizing the mutual Hamming distance in $\big[{\cal P}([n])\big]^n$
awarded
 Yearling
accepted
Density of perfect numbers
asked
Density of perfect numbers
accepted
Cardinality of separating families on an infinite cardinal $\kappa$
asked
Cardinality of separating families on an infinite cardinal $\kappa$
comment
Relation between two different definitions for relative sequential compactness
Sorry @BoazTsaban, I have seen your request "a little later" (8 years), will write something on that soon, hopefully
accepted
Bijection $f:\mathbb{N}\to\mathbb{N}$ such that $f(S)\neq S$ for $S\subseteq \mathbb{N}$ infinite and co-infinite
asked
Bijection $f:\mathbb{N}\to\mathbb{N}$ such that $f(S)\neq S$ for $S\subseteq \mathbb{N}$ infinite and co-infinite
accepted
$|S\cap f(S)|$ for bijections $f:\omega\to\omega$ and $S\subseteq \omega$
asked
$|S\cap f(S)|$ for bijections $f:\omega\to\omega$ and $S\subseteq \omega$
accepted
Image-catching families in $\omega$
revised
Is it consistent that $|[\kappa]^{<\kappa}| > \kappa$?
added 7 characters in body
comment
Is it consistent that $|[\kappa]^{<\kappa}| > \kappa$?
Right, @bof, will correct
comment
Image-catching families in $\omega$
Very nice answer, thanks FarmerS! If I understand correctly, then under MA (and also, trivially, CH) every image-catching family had cardinality $\frak c$, but we don't know yet whether this is provably true in $\sf (ZFC)$. Di I wait a short time before accepting the answer if this is okay for you
asked
Image-catching families in $\omega$
accepted
Smallest ${\mathbf B}$-function $f:\omega\to( \omega\setminus\{0\})$
comment
Smallest ${\mathbf B}$-function $f:\omega\to( \omega\setminus\{0\})$
Thank you to both Andreas and bof. Can you post your comment as an answer, bof?
revised
Smallest ${\mathbf B}$-function $f:\omega\to( \omega\setminus\{0\})$
added 170 characters in body; edited title
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