For a graph G and a family of graphs
$\mathcal {F}$
, the Turán number
${\mathrm {ex}}(G,\mathcal {F})$
is the maximum number of edges an
$\mathcal {F}$
-free subgraph of G can have. We prove that
${\mathrm {ex}}(G,\mathcal {F})\ge {\mathrm {ex}}(K_r, \mathcal {F})$
if the chromatic number of G is r and
$\mathcal {F}$
is a family of connected graphs. This result answers a question raised by Briggs and Cox [‘Inverting the Turán problem’, Discrete Math.342(7) (2019), 1865–1884] about the inverse Turán number for all connected graphs.
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