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 $\kappa $-HOMOGENEOUS, BUT NOT
$\kappa $-HOMOGENEOUS, BUT NOT  $\kappa $-TRANSITIVE PERMUTATION GROUPS
$\kappa $-TRANSITIVE PERMUTATION GROUPSPublished online by Cambridge University Press: 13 August 2021
A permutation group G on a set A is  ${\kappa }$-homogeneous iff for all
${\kappa }$-homogeneous iff for all  $X,Y\in \bigl [ {A} \bigr ]^ {\kappa } $ with
$X,Y\in \bigl [ {A} \bigr ]^ {\kappa } $ with  $|A\setminus X|=|A\setminus Y|=|A|$ there is a
$|A\setminus X|=|A\setminus Y|=|A|$ there is a  $g\in G$ with
$g\in G$ with  $g[X]=Y$. G is
$g[X]=Y$. G is  ${\kappa }$-transitive iff for any injective function f with
${\kappa }$-transitive iff for any injective function f with  $\operatorname {dom}(f)\cup \operatorname {ran}(f)\in \bigl [ {A} \bigr ]^ {\le {\kappa }} $ and
$\operatorname {dom}(f)\cup \operatorname {ran}(f)\in \bigl [ {A} \bigr ]^ {\le {\kappa }} $ and  $|A\setminus \operatorname {dom}(f)|=|A\setminus \operatorname {ran}(f)|=|A|$ there is a
$|A\setminus \operatorname {dom}(f)|=|A\setminus \operatorname {ran}(f)|=|A|$ there is a  $g\in G$ with
$g\in G$ with  $f\subset g$.
$f\subset g$.
Giving a partial answer to a question of P. M. Neumann [6] we show that there is an  ${\omega }$-homogeneous but not
${\omega }$-homogeneous but not  ${\omega }$-transitive permutation group on a cardinal
${\omega }$-transitive permutation group on a cardinal  ${\lambda }$ provided
${\lambda }$ provided 
(i)  ${\lambda }<{\omega }_{\omega }$, or
${\lambda }<{\omega }_{\omega }$, or
(ii)  $2^{\omega }<{\lambda }$, and
$2^{\omega }<{\lambda }$, and  ${\mu }^{\omega }={\mu }^+$ and
${\mu }^{\omega }={\mu }^+$ and  $\Box _{\mu }$ hold for each
$\Box _{\mu }$ hold for each  ${\mu }\le {\lambda }$ with
${\mu }\le {\lambda }$ with  ${\omega }=\operatorname {cf}({\mu })<{{\mu }}$, or
${\omega }=\operatorname {cf}({\mu })<{{\mu }}$, or
(iii) our model was obtained by adding  $(2^{\omega })^+$ many Cohen generic reals to some ground model.
$(2^{\omega })^+$ many Cohen generic reals to some ground model.
For  ${\kappa }>{\omega }$ we give a method to construct large
${\kappa }>{\omega }$ we give a method to construct large  ${\kappa }$-homogeneous, but not
${\kappa }$-homogeneous, but not  ${\kappa }$-transitive permutation groups. Using this method we show that there exist
${\kappa }$-transitive permutation groups. Using this method we show that there exist  ${\kappa }^+$-homogeneous, but not
${\kappa }^+$-homogeneous, but not  ${\kappa }^+$-transitive permutation groups on
${\kappa }^+$-transitive permutation groups on  ${\kappa }^{+n}$ for each infinite cardinal
${\kappa }^{+n}$ for each infinite cardinal  ${\kappa }$ and natural number
${\kappa }$ and natural number  $n\ge 1$ provided
$n\ge 1$ provided  $V=L$.
$V=L$.