<p>Let <InlineEquation ID="IEq1"> <EquationSource Format="TEX">\({\mathcal {H}}\)</EquationSource> <EquationSource Format="MATHML"><math> <mi mathvariant="script">H</mi> </math></EquationSource> </InlineEquation> be a <i>k</i>-uniform hypergraph on <i>n</i> vertices. For a fixed positive integer <i>s</i>, the most natural way to define a subhypergraph of <InlineEquation ID="IEq2"> <EquationSource Format="TEX">\({\mathcal {H}}\)</EquationSource> <EquationSource Format="MATHML"><math> <mi mathvariant="script">H</mi> </math></EquationSource> </InlineEquation> without <InlineEquation ID="IEq3"> <EquationSource Format="TEX">\(s + 1\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>s</mi> <mo>+</mo> <mn>1</mn> </mrow> </math></EquationSource> </InlineEquation> pairwise disjoint edges is to take all edges containing at least one of <i>s</i> fixed vertices. We prove that for <InlineEquation ID="IEq4"> <EquationSource Format="TEX">\(n > n_0(k, s)\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>n</mi> <mo>></mo> <msub> <mi>n</mi> <mn>0</mn> </msub> <mrow> <mo stretchy="false">(</mo> <mi>k</mi> <mo>,</mo> <mi>s</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> and a relatively wide class of hypergraphs this construction is the largest.</p>
On the maximum size of substructures with fixed matching number
Let \({\mathcal {H}}\) be a k-uniform hypergraph on n vertices. For a fixed positive integer s, the most natural way to define a subhypergraph of \({\mathcal {H}}\) without \(s + 1\) pairwise disjoint edges is to take all edges containing at least one of s fixed vertices. We prove that for \(n > n_0(k, s)\) and a relatively wide class of hypergraphs this construction is the largest.