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A hypergraph
$\mathcal{F}$
is non-trivial intersecting if every pair of edges in it have a nonempty intersection, but no vertex is contained in all edges of
$\mathcal{F}$
. Mubayi and Verstraëte showed that for every
$k \ge d+1 \ge 3$
and
$n \ge (d+1)k/d$
every
$k$
-graph
$\mathcal{H}$
on
$n$
vertices without a non-trivial intersecting subgraph of size
$d+1$
contains at most
$\binom{n-1}{k-1}$
edges. They conjectured that the same conclusion holds for all
$d \ge k \ge 4$
and sufficiently large
$n$
. We confirm their conjecture by proving a stronger statement.
They also conjectured that for
$m \ge 4$
and sufficiently large
$n$
the maximum size of a
$3$
-graph on
$n$
vertices without a non-trivial intersecting subgraph of size
$3m+1$
is achieved by certain Steiner triple systems. We give a construction with more edges showing that their conjecture is not true in general.
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