Matching Tag: kneser-hypergraphs
Let K G r ( n , k ) KG^r(n,k) K G r ( n , k ) be the Kneser hypergraph whose vertices are the k k k -element subsets of [ n ] [n] [ n ] , and call a subset S ⊆ [ n ] S\subseteq[n] S ⊆ [ n ] r r r -stable when any two elements x , y ∈ S x,y\in S x , y ∈ S satisfy…
Let [ n ] = { 1 , … , n } [n]=\{1,\ldots,n\} [ n ] = { 1 , … , n } , and let K G r ( n , k ) s -stab \mathrm{KG}^r(n,k)_{s\textup{-stab}} KG r ( n , k ) s -stab be the induced r r r -uniform Kneser hypergraph whose vertices are the s s s -stable k k k -subsets of [ n ] [n] [ n ] , where…
Let [ n ] = { 1 , … , n } [n]=\{1,\ldots,n\} [ n ] = { 1 , … , n } , let G \mathcal G G be a hypergraph over the ground set [ n ] [n] [ n ] , and let r ≥ s ≥ 2 r\geq s\geq 2 r ≥ s ≥ 2 . Write G { s -stable } ~ \mathcal G_{\widetilde{\{s\text{-stable}\}}} G { s -stable } for the correspo…
Let r ≥ 2 r\geq 2 r ≥ 2 and let F \mathcal{F} F be a set system. Write F r − stab ~ \mathcal{F}_{\widetilde{r-\operatorname{stab}}} F r − stab for the family obtained by retaining the source's weakened notion of…
Let n ≥ 1 n\ge 1 n ≥ 1 , r ≥ 2 r\ge 2 r ≥ 2 , and s ≥ r s\ge r s ≥ r , and let F \cal F F be a family of subsets of [ n ] [n] [ n ] . For the almost s s s -stable subfamily F s \cal F_s F s , let KG r ( F s ) \operatorname{KG}^r(\cal F_s) KG r ( F s ) be the…
Let q q q be a positive integer, and let P P P be a path whose vertex set is partitioned into m m m subsets V 1 , … , V m V_1,\dots,V_m V 1 , … , V m , each of size at least q − 1 q-1 q − 1 . A set of vertices is q q q -stable…
Let A ⊂ [ n ] A\subset[n] A ⊂ [ n ] , and let K G A r ( n , k ) \mathrm{KG}^r_A(n,k) KG A r ( n , k ) be the subhypergraph of the r r r -uniform Kneser hypergraph induced by the k k k -subsets σ ⊂ [ n ] \sigma\subset[n] σ ⊂ [ n ] with σ ⊄ A \sigma\not\subset A σ ⊂ A …
Let r ≥ 2 r\ge 2 r ≥ 2 , k ≥ 1 k\ge 1 k ≥ 1 , and n ≥ r k n\ge rk n ≥ r k be integers, and let P = { P 1 , … , P ℓ } \mathcal P=\{P_1,\dots,P_\ell\} P = { P 1 , … , P ℓ } be a partition of [ n ] [n] [ n ] such that ∣ P i ∣ ≤ r |P_i|\le r ∣ P i ∣ ≤ r for every i i i . Let…
For positive integers n , k , r n,k,r n , k , r with k ≥ 2 k\geq 2 k ≥ 2 , r ≥ 2 r\geq 2 r ≥ 2 , and n ≥ r k n\geq rk n ≥ r k , let K G r ( n , k ) r - s t a b KG^{r}(n,k)_{r\text{-}stab} K G r ( n , k ) r - s t ab be the r r r -stable r r r -uniform Kneser hypergraph, and let K G r ( n , k ) KG^{r}(n,k) K G r ( n , k ) be…
Ziegler–Alon–Drewnowski–Łuczak conjecture.
Let G = ( V , E ) \mathcal{G}=(V,E) G = ( V , E ) and G ′ = ( V ′ , E ′ ) \mathcal{G}'=(V',E') G ′ = ( V ′ , E ′ ) be hypergraphs. Their categorical product G × G ′ \mathcal{G}\times\mathcal{G}' G × G ′ has vertex set V × V ′ V\times V' V × V ′ and edges whose projections…