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Jones' conjecture ★★

Author(s): Kloks; Lee; Liu

For a graph $ G $, let $ cp(G) $ denote the cardinality of a maximum cycle packing (collection of vertex disjoint cycles) and let $ cc(G) $ denote the cardinality of a minimum feedback vertex set (set of vertices $ X $ so that $ G-X $ is acyclic).

Conjecture   For every planar graph $ G $, $ cc(G)\leq 2cp(G) $.

Keywords: cycle packing; feedback vertex set; planar graph

Funcoidal products inside an inward reloid ★★

Author(s): Porton

Conjecture   (solved) If $ a \times^{\mathsf{\ensuremath{\operatorname{RLD}}}} b \subseteq \left( \mathsf{\ensuremath{\operatorname{RLD}}} \right)_{\ensuremath{\operatorname{in}}} f $ then $ a \times^{\mathsf{\ensuremath{\operatorname{FCD}}}} b \subseteq f $ for every funcoid $ f $ and atomic f.o. $ a $ and $ b $ on the source and destination of $ f $ correspondingly.

A stronger conjecture:

Conjecture   If $ \mathcal{A} \times^{\mathsf{\ensuremath{\operatorname{RLD}}}} \mathcal{B} \subseteq \left( \mathsf{\ensuremath{\operatorname{RLD}}} \right)_{\ensuremath{\operatorname{in}}} f $ then $ \mathcal{A} \times^{\mathsf{\ensuremath{\operatorname{FCD}}}} \mathcal{B} \subseteq f $ for every funcoid $ f $ and $ \mathcal{A} \in \mathfrak{F} \left( \ensuremath{\operatorname{Src}}f \right) $, $ \mathcal{B} \in \mathfrak{F} \left( \ensuremath{\operatorname{Dst}}f \right) $.

Keywords: inward reloid

Edge-antipodal colorings of cubes ★★

Author(s): Norine

We let $ Q_d $ denote the $ d $-dimensional cube graph. A map $ \phi : E(Q_d) \rightarrow \{0,1\} $ is called edge-antipodal if $ \phi(e) \neq \phi(e') $ whenever $ e,e' $ are antipodal edges.

Conjecture   If $ d \ge 2 $ and $ \phi : E(Q_d) \rightarrow \{0,1\} $ is edge-antipodal, then there exist a pair of antipodal vertices $ v,v' \in V(Q_d) $ which are joined by a monochromatic path.

Keywords: antipodal; cube; edge-coloring

Olson's Conjecture ★★

Author(s): Olson

Conjecture   If $ a_1,a_2,\ldots,a_{2n-1} $ is a sequence of elements from a multiplicative group of order $ n $, then there exist $ 1 \le j_1 < j_2 \ldots < j_n \le 2n-1 $ so that $ \prod_{i=1}^n a_{j_i} = 1 $.

Keywords: zero sum

Weighted colouring of hexagonal graphs. ★★

Author(s): McDiarmid; Reed

Conjecture   There is an absolute constant $ c $ such that for every hexagonal graph $ G $ and vertex weighting $ p:V(G)\rightarrow \mathbb{N} $, $$\chi(G,p) \leq \frac{9}{8}\omega(G,p) + c $$

Keywords:

Kriesell's Conjecture ★★

Author(s): Kriesell

Conjecture   Let $ G $ be a graph and let $ T\subseteq V(G) $ such that for any pair $ u,v\in T $ there are $ 2k $ edge-disjoint paths from $ u $ to $ v $ in $ G $. Then $ G $ contains $ k $ edge-disjoint trees, each of which contains $ T $.

Keywords: Disjoint paths; edge-connectivity; spanning trees

List Hadwiger Conjecture ★★

Author(s): Kawarabayashi; Mohar

Conjecture   Every $ K_t $-minor-free graph is $ c t $-list-colourable for some constant $ c\geq1 $.

Keywords: Hadwiger conjecture; list colouring; minors

Jacob Palis Conjecture(Finitude of Attractors)(Dynamical Systems) ★★★★

Author(s):

Conjecture   Let $ Diff^{r}(M)  $ be the space of $ C^{r} $ Diffeomorphisms on the connected , compact and boundaryles manifold M and $ \chi^{r}(M) $ the space of $ C^{r} $ vector fields. There is a dense set $ D\subset Diff^{r}(M) $ ($ D\subset \chi^{r}(M) $ ) such that $ \forall f\in D $ exhibit a finite number of attractor whose basins cover Lebesgue almost all ambient space $ M $

This is a very Deep and Hard problem in Dynamical Systems . It present the dream of the dynamicist mathematicians .

Keywords: Attractors , basins, Finite

Gardenscapes Cheats Generator Free Cheats Generator 2024 No Verification (Android iOS) ★★

Author(s):

Gardenscapes Cheats Generator Free Cheats Generator 2024 No Verification (Android iOS)

Keywords:

Golf Battle Free Cheats Generator 999,999k Free 2024 (Free Generator) ★★

Author(s):

Golf Battle Free Cheats Generator 999,999k Free 2024 (Free Generator)

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Monotone 4-term Arithmetic Progressions ★★

Author(s): Davis; Entringer; Graham; Simmons

Question   Is it true that every permutation of positive integers must contain monotone 4-term arithmetic progressions?

Keywords: monotone arithmetic progression; permutation

Choice Number of k-Chromatic Graphs of Bounded Order ★★

Author(s): Noel

Conjecture   If $ G $ is a $ k $-chromatic graph on at most $ mk $ vertices, then $ \text{ch}(G)\leq \text{ch}(K_{m*k}) $.

Keywords: choosability; complete multipartite graph; list coloring

List Total Colouring Conjecture ★★

Author(s): Borodin; Kostochka; Woodall

Conjecture   If $ G $ is the total graph of a multigraph, then $ \chi_\ell(G)=\chi(G) $.

Keywords: list coloring; Total coloring; total graphs

Cycle double cover conjecture ★★★★

Author(s): Seymour; Szekeres

Conjecture   For every graph with no bridge, there is a list of cycles so that every edge is contained in exactly two.

Keywords: cover; cycle

Decomposing k-arc-strong tournament into k spanning strong digraphs ★★

Author(s): Bang-Jensen; Yeo

Conjecture   Every k-arc-strong tournament decomposes into k spanning strong digraphs.

Keywords:

Match Masters Free Coins Cheats 2024 (FREE!) ★★

Author(s):

Match Masters Free Coins Cheats 2024 (FREE!)

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Wall-Sun-Sun primes and Fibonacci divisibility ★★

Author(s):

Conjecture   For any prime $ p $, there exists a Fibonacci number divisible by $ p $ exactly once.

Equivalently:

Conjecture   For any prime $ p>5 $, $ p^2 $ does not divide $ F_{p-\left(\frac p5\right)} $ where $ \left(\frac mn\right) $ is the Legendre symbol.

Keywords: Fibonacci; prime

Cooking Fever Cheats Generator Free 2024 in 5 minutes (New Cheats Generator Cooking Fever) ★★

Author(s):

Cooking Fever Cheats Generator Free 2024 in 5 minutes (New Cheats Generator Cooking Fever)

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Brawlhalla Cheats Generator 2024 Real Working (new method) ★★

Author(s):

Brawlhalla Cheats Generator 2024 Real Working (new method)

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Reconstruction conjecture ★★★★

Author(s): Kelly; Ulam

The deck of a graph $ G $ is the multiset consisting of all unlabelled subgraphs obtained from $ G $ by deleting a vertex in all possible ways (counted according to multiplicity).

Conjecture   If two graphs on $ \ge 3 $ vertices have the same deck, then they are isomorphic.

Keywords: reconstruction

Working Apex Legends Cheats Online Coins Generator (No Survey) ★★

Author(s):

Working Apex Legends Cheats Online Coins Generator (No Survey)

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Coloring and immersion ★★★

Author(s): Abu-Khzam; Langston

Conjecture   For every positive integer $ t $, every (loopless) graph $ G $ with $ \chi(G) \ge t $ immerses $ K_t $.

Keywords: coloring; complete graph; immersion

Warframe Free Platinum Cheats Free Generator 2024 in 5 minutes (successive cheats) ★★

Author(s):

Warframe Free Platinum Cheats Free Generator 2024 in 5 minutes (successive cheats)

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Decomposing eulerian graphs ★★★

Author(s):

Conjecture   If $ G $ is a 6-edge-connected Eulerian graph and $ P $ is a 2-transition system for $ G $, then $ (G,P) $ has a compaible decomposition.

Keywords: cover; cycle; Eulerian

A sextic counterexample to Euler's sum of powers conjecture ★★

Author(s): Euler

Problem   Find six positive integers $ x_1, x_2, \dots, x_6 $ such that $$x_1^6 + x_2^6 + x_3^6 + x_4^6 + x_5^6 = x_6^6$$ or prove that such integers do not exist.

Keywords:

Erdős–Faber–Lovász conjecture ★★★

Author(s): Erdos; Faber; Lovasz

Conjecture   If $ G $ is a simple graph which is the union of $ k $ pairwise edge-disjoint complete graphs, each of which has $ k $ vertices, then the chromatic number of $ G $ is $ k $.

Keywords: chromatic number

"Working Cheats" Sims FreePlay Simoleons Life Points and Social Points Generator No Human Verification 2024 ★★

Author(s):

"Working Cheats" Sims FreePlay Simoleons Life Points and Social Points Generator No Human Verification 2024

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Partial List Coloring ★★★

Author(s): Iradmusa

Let $ G $ be a simple graph, and for every list assignment $ \mathcal{L} $ let $ \lambda_{\mathcal{L}} $ be the maximum number of vertices of $ G $ which are colorable with respect to $ \mathcal{L} $. Define $ \lambda_t = \min{ \lambda_{\mathcal{L}} } $, where the minimum is taken over all list assignments $ \mathcal{L} $ with $ |\mathcal{L}| = t $ for all $ v \in V(G) $.

Conjecture   [2] Let $ G $ be a graph with list chromatic number $ \chi_\ell $ and $ 1\leq r\leq s\leq \chi_\ell $. Then \[\frac{\lambda_r}{r}\geq\frac{\lambda_s}{s}.\]

Keywords: list assignment; list coloring

Highly connected graphs with no K_n minor ★★★

Author(s): Thomas

Problem   Is it true for all $ n \ge 0 $, that every sufficiently large $ n $-connected graph without a $ K_n $ minor has a set of $ n-5 $ vertices whose deletion results in a planar graph?

Keywords: connectivity; minor

Complete bipartite subgraphs of perfect graphs ★★

Author(s): Fox

Problem   Let $ G $ be a perfect graph on $ n $ vertices. Is it true that either $ G $ or $ \bar{G} $ contains a complete bipartite subgraph with bipartition $ (A,B) $ so that $ |A|, |B| \ge n^{1 - o(1)} $?

Keywords: perfect graph

Partitioning edge-connectivity ★★

Author(s): DeVos

Question   Let $ G $ be an $ (a+b+2) $-edge-connected graph. Does there exist a partition $ \{A,B\} $ of $ E(G) $ so that $ (V,A) $ is $ a $-edge-connected and $ (V,B) $ is $ b $-edge-connected?

Keywords: edge-coloring; edge-connectivity

Invariant subspace problem ★★★

Author(s):

Problem   Does every bounded linear operator on an infinite-dimensional separable Hilbert space have a non-trivial closed invariant subspace?

Keywords: subspace

Long directed cycles in diregular digraphs ★★★

Author(s): Jackson

Conjecture   Every strong oriented graph in which each vertex has indegree and outdegree at least $ d $ contains a directed cycle of length at least $ 2d+1 $.

Keywords:

List colorings of edge-critical graphs ★★

Author(s): Mohar

Conjecture   Suppose that $ G $ is a $ \Delta $-edge-critical graph. Suppose that for each edge $ e $ of $ G $, there is a list $ L(e) $ of $ \Delta $ colors. Then $ G $ is $ L $-edge-colorable unless all lists are equal to each other.

Keywords: edge-coloring; list coloring

Legal SimCity BuildIt Cheats Generator No Human Verification 2024 (No Surveys Needed) ★★

Author(s):

Legal SimCity BuildIt Cheats Generator No Human Verification 2024 (No Surveys Needed)

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Rank vs. Genus ★★★

Author(s): Johnson

Question   Is there a hyperbolic 3-manifold whose fundamental group rank is strictly less than its Heegaard genus? How much can the two differ by?

Keywords:

Graceful Tree Conjecture ★★★

Author(s):

Conjecture   All trees are graceful

Keywords: combinatorics; graceful labeling

Legal* Free Coin Master Cheats Spins Coins Generator No Human Verification 2024 ★★

Author(s):

Legal* Free Coin Master Cheats Spins Coins Generator No Human Verification 2024

Keywords:

V-Bucks Generator Free 2024 in 5 minutes (New Generator V-Bucks) ★★

Author(s):

V-Bucks Generator Free 2024 in 5 minutes (New Generator V-Bucks)

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Divisibility of central binomial coefficients ★★

Author(s): Graham

Problem  (1)   Prove that there exist infinitely many positive integers $ n $ such that $$\gcd({2n\choose n}, 3\cdot 5\cdot 7) = 1.$$
Problem  (2)   Prove that there exists only a finite number of positive integers $ n $ such that $$\gcd({2n\choose n}, 3\cdot 5\cdot 7\cdot 11) = 1.$$

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Cooking Fever Cheats Generator Latest Version 2024 For Free (WORKING Generator) ★★

Author(s):

Cooking Fever Cheats Generator Latest Version 2024 For Free (WORKING Generator)

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Jurassic Park Builder Cheats Generator 2024 No Human Verification (Real) ★★

Author(s):

Jurassic Park Builder Cheats Generator 2024 No Human Verification (Real)

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Bingo Blitz Cheats Generator iOS Android (Current 2024 Generator) ★★

Author(s):

Bingo Blitz Cheats Generator iOS Android (Current 2024 Generator)

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Royal Match Free Coins Cheats 2024 Real Working New Method ★★

Author(s):

Royal Match Free Coins Cheats 2024 Real Working New Method

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Free Clash of Clans Cheats Gems Generator 2023-2024 ★★

Author(s):

Free Clash of Clans Cheats Gems Generator 2023-2024

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Working Generator World Of Tanks Blitz Gold Credits Cheats Android Ios 2024 (HOT) ★★

Author(s):

Working Generator World Of Tanks Blitz Gold Credits Cheats Android Ios 2024 (HOT)

Keywords:

Erdős-Posa property for long directed cycles ★★

Author(s): Havet; Maia

Conjecture   Let $ \ell \geq 2 $ be an integer. For every integer $ n\geq 0 $, there exists an integer $ t_n=t_n(\ell) $ such that for every digraph $ D $, either $ D $ has a $ n $ pairwise-disjoint directed cycles of length at least $ \ell $, or there exists a set $ T $ of at most $ t_n $ vertices such that $ D-T $ has no directed cycles of length at least $ \ell $.

Keywords:

Hall-Paige conjecture (Solved) ★★

Author(s):

Hall-Paige conjecture (Solved)

Keywords:

Singmaster's conjecture ★★

Author(s): Singmaster

Conjecture   There is a finite upper bound on the multiplicities of entries in Pascal's triangle, other than the number $ 1 $.

The number $ 2 $ appears once in Pascal's triangle, $ 3 $ appears twice, $ 6 $ appears three times, and $ 10 $ appears $ 4 $ times. There are infinite families of numbers known to appear $ 6 $ times. The only number known to appear $ 8 $ times is $ 3003 $. It is not known whether any number appears more than $ 8 $ times. The conjectured upper bound could be $ 8 $; Singmaster thought it might be $ 10 $ or $ 12 $. See Singmaster's conjecture.

Keywords: Pascal's triangle

Geodesic cycles and Tutte's Theorem ★★

Author(s): Georgakopoulos; Sprüssel

Problem   If $ G $ is a $ 3 $-connected finite graph, is there an assignment of lengths $ \ell: E(G) \to \mathb R^+ $ to the edges of $ G $, such that every $ \ell $-geodesic cycle is peripheral?

Keywords: cycle space; geodesic cycles; peripheral cycles