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Odd-cycle transversal in triangle-free graphs ★★

Author(s): Erdos; Faudree; Pach; Spencer

Conjecture   If $ G $ is a simple triangle-free graph, then there is a set of at most $ n^2/25 $ edges whose deletion destroys every odd cycle.

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World of Warships Cheats Generator Fully Works No Survey Cheats Generator (2024) ★★

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World of Warships Cheats Generator Fully Works No Survey Cheats Generator (2024)

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Bingo Blitz Cheats Generator Unlimited No Jailbreak (Premium) ★★

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Bingo Blitz Cheats Generator Unlimited No Jailbreak (Premium)

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Free Hollywood Story Free Diamonds Gems Cheats 2024 (Safe) ★★

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Free Hollywood Story Free Diamonds Gems Cheats 2024 (Safe)

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Highly arc transitive two ended digraphs ★★

Author(s): Cameron; Praeger; Wormald

Conjecture   If $ G $ is a highly arc transitive digraph with two ends, then every tile of $ G $ is a disjoint union of complete bipartite graphs.

Keywords: arc transitive; digraph; infinite graph

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?

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Circular flow number of regular class 1 graphs ★★

Author(s): Steffen

A nowhere-zero $ r $-flow $ (D(G),\phi) $ on $ G $ is an orientation $ D $ of $ G $ together with a function $ \phi $ from the edge set of $ G $ into the real numbers such that $ 1 \leq |\phi(e)| \leq r-1 $, for all $ e \in E(G) $, and $ \sum_{e \in E^+(v)}\phi(e) = \sum_{e \in E^-(v)}\phi(e), \textrm{ for all } v \in V(G) $. The circular flow number of $ G $ is inf$ \{ r | G $ has a nowhere-zero $ r $-flow $ \} $, and it is denoted by $ F_c(G) $.

A graph with maximum vertex degree $ k $ is a class 1 graph if its edge chromatic number is $ k $.

Conjecture   Let $ t \geq 1 $ be an integer and $ G $ a $ (2t+1) $-regular graph. If $ G $ is a class 1 graph, then $ F_c(G) \leq 2 + \frac{2}{t} $.

Keywords: nowhere-zero flow, edge-colorings, regular graphs

Direct proof of a theorem about compact funcoids ★★

Author(s): Porton

Conjecture   Let $ f $ is a $ T_1 $-separable (the same as $ T_2 $ for symmetric transitive) compact funcoid and $ g $ is a uniform space (reflexive, symmetric, and transitive endoreloid) such that $ ( \mathsf{\tmop{FCD}}) g = f $. Then $ g = \langle f \times f \rangle^{\ast} \Delta $.

The main purpose here is to find a direct proof of this conjecture. It seems that this conjecture can be derived from the well known theorem about existence of exactly one uniformity on a compact set. But that would be what I call an indirect proof, we need a direct proof instead.

The direct proof may be constructed by correcting all errors an omissions in this draft article.

Direct proof could be better because with it we would get a little more general statement like this:

Conjecture   Let $ f $ be a $ T_1 $-separable compact reflexive symmetric funcoid and $ g $ be a reloid such that
    \item $ ( \mathsf{\tmop{FCD}}) g = f $; \item $ g \circ g^{- 1} \sqsubseteq g $.

Then $ g = \langle f \times f \rangle^{\ast} \Delta $.

Keywords: compact space; compact topology; funcoid; reloid; uniform space; uniformity

Family Island Cheats Generator 2024 No Human Verification (Real) ★★

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Family Island Cheats Generator 2024 No Human Verification (Real)

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Free Bloons TD Battles Energy Medal Money Cheats Pro Apk 2024 (Android Ios) ★★

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Free Bloons TD Battles Energy Medal Money Cheats Pro Apk 2024 (Android Ios)

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Elementary symmetric of a sum of matrices ★★★

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Problem  

Given a Matrix $ A $, the $ k $-th elementary symmetric function of $ A $, namely $ S_k(A) $, is defined as the sum of all $ k $-by-$ k $ principal minors.

Find a closed expression for the $ k $-th elementary symmetric function of a sum of N $ n $-by-$ n $ matrices, with $ 0\le N\le k\le n $ by using partitions.

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Termination of the sixth Goodstein Sequence

Author(s): Graham

Question   How many steps does it take the sixth Goodstein sequence to terminate?

Keywords: Goodstein Sequence

The three 4-flows conjecture ★★

Author(s): DeVos

Conjecture   For every graph $ G $ with no bridge, there exist three disjoint sets $ A_1,A_2,A_3 \subseteq E(G) $ with $ A_1 \cup A_2 \cup A_3 = E(G) $ so that $ G \setminus A_i $ has a nowhere-zero 4-flow for $ 1 \le i \le 3 $.

Keywords: nowhere-zero flow

Every metamonovalued reloid is monovalued ★★

Author(s): Porton

Conjecture   Every metamonovalued reloid is monovalued.

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Hamiltonian paths and cycles in vertex transitive graphs ★★★

Author(s): Lovasz

Problem   Does every connected vertex-transitive graph have a Hamiltonian path?

Keywords: cycle; hamiltonian; path; vertex-transitive

Unions of triangle free graphs ★★★

Author(s): Erdos; Hajnal

Problem   Does there exist a graph with no subgraph isomorphic to $ K_4 $ which cannot be expressed as a union of $ \aleph_0 $ triangle free graphs?

Keywords: forbidden subgraph; infinite graph; triangle free

Oriented chromatic number of planar graphs ★★

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An oriented colouring of an oriented graph is assignment $ c $ of colours to the vertices such that no two arcs receive ordered pairs of colours $ (c_1,c_2) $ and $ (c_2,c_1) $. It is equivalent to a homomorphism of the digraph onto some tournament of order $ k $.

Problem   What is the maximal possible oriented chromatic number of an oriented planar graph?

Keywords: oriented coloring; oriented graph; planar graph

Geometry Dash Gold Coins Stars Cheats 2024 Update (FREE!!) ★★

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Geometry Dash Gold Coins Stars Cheats 2024 Update (FREE!!)

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Are almost all graphs determined by their spectrum? ★★★

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Problem   Are almost all graphs uniquely determined by the spectrum of their adjacency matrix?

Keywords: cospectral; graph invariant; spectrum

Brawlhalla Cheats Generator 2024 No Human Veryfication (codes) ★★

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Brawlhalla Cheats Generator 2024 No Human Veryfication (codes)

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5-flow conjecture ★★★★

Author(s): Tutte

Conjecture   Every bridgeless graph has a nowhere-zero 5-flow.

Keywords: cubic; nowhere-zero flow

Free Kim Kardashian Hollywood Cash Stars Cheats Pro Apk 2024 (Android Ios) ★★

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Free Kim Kardashian Hollywood Cash Stars Cheats Pro Apk 2024 (Android Ios)

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Burnside problem ★★★★

Author(s): Burnside

Conjecture   If a group has $ r $ generators and exponent $ n $, is it necessarily finite?

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Woodall's Conjecture ★★★

Author(s): Woodall

Conjecture   If $ G $ is a directed graph with smallest directed cut of size $ k $, then $ G $ has $ k $ disjoint dijoins.

Keywords: digraph; packing

Odd cycles and low oddness ★★

Author(s):

Conjecture   If in a bridgeless cubic graph $ G $ the cycles of any $ 2 $-factor are odd, then $ \omega(G)\leq 2 $, where $ \omega(G) $ denotes the oddness of the graph $ G $, that is, the minimum number of odd cycles in a $ 2 $-factor of $ G $.

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Yu Gi Oh Duel Links Cheats Generator 2024 (No Human Verification) ★★

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Yu Gi Oh Duel Links Cheats Generator 2024 (No Human Verification)

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eFootball 2023 Cheats Generator Unlimited IOS Android No Survey 2024 (FREE METHOD) ★★

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eFootball 2023 Cheats Generator Unlimited IOS Android No Survey 2024 (FREE METHOD)

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Working My Singing Monsters Cheats Generator Online (No Survey) ★★

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Working My Singing Monsters Cheats Generator Online (No Survey)

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Easy! Unlimited Rise Of Kingdoms Cheats Generator codes (GLITCH) ★★

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Easy! Unlimited Rise Of Kingdoms Cheats Generator codes (GLITCH)

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MONOPOLY GO Cheats Generator 2024 (Legal) ★★

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MONOPOLY GO Cheats Generator 2024 (Legal)

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Rise Of Kingdoms Cheats Generator 2023-2024 Edition (Verified) ★★

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Rise Of Kingdoms Cheats Generator 2023-2024 Edition (Verified)

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Decomposing an eulerian graph into cycles. ★★

Author(s): Hajós

Conjecture   Every simple eulerian graph on $ n $ vertices can be decomposed into at most $ \frac{1}{2}(n-1) $ cycles.

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r-regular graphs are not uniquely hamiltonian. ★★★

Author(s): Sheehan

Conjecture   If $ G $ is a finite $ r $-regular graph, where $ r > 2 $, then $ G $ is not uniquely hamiltonian.

Keywords: hamiltonian; regular; uniquely hamiltonian

Free Royal Match Free Coins Cheats 2024 (Safe) ★★

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Free Royal Match Free Coins Cheats 2024 (Safe)

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Total Colouring Conjecture ★★★

Author(s): Behzad

Conjecture   A total coloring of a graph $ G = (V,E) $ is an assignment of colors to the vertices and the edges of $ G $ such that every pair of adjacent vertices, every pair of adjacent edges and every vertex and incident edge pair, receive different colors. The total chromatic number of a graph $ G $, $ \chi''(G) $, equals the minimum number of colors needed in a total coloring of $ G $. It is an old conjecture of Behzad that for every graph $ G $, the total chromatic number equals the maximum degree of a vertex in $ G $, $ \Delta(G) $ plus one or two. In other words, \[\chi''(G)=\Delta(G)+1\ \ or \ \ \Delta(G)+2.\]

Keywords: Total coloring

Hungry Shark Evolution Cheats Generator IOS Android No Survey 2024 (Generator!) ★★

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Hungry Shark Evolution Cheats Generator IOS Android No Survey 2024 (Generator!)

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New War Dragons Free Rubies Cheats 2024 Tested (extra) ★★

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New War Dragons Free Rubies Cheats 2024 Tested (extra)

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Special Primes

Author(s): George BALAN

Conjecture   Let $ p $ be a prime natural number. Find all primes $ q\equiv1\left(\mathrm{mod}\: p\right) $, such that $ 2^{\frac{\left(q-1\right)}{p}}\equiv1\left(\mathrm{mod}\: q\right) $.

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Idle Miner Tycoon Cheats Generator Pro Apk (Android Ios) ★★

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Idle Miner Tycoon Cheats Generator Pro Apk (Android Ios)

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Ádám's Conjecture ★★★

Author(s): Ádám

Conjecture   Every digraph with at least one directed cycle has an arc whose reversal reduces the number of directed cycles.

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Fishdom Cheats Generator without verification (Free) ★★

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Fishdom Cheats Generator without verification (Free)

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Generalised Empty Hexagon Conjecture ★★

Author(s): Wood

Conjecture   For each $ \ell\geq3 $ there is an integer $ f(\ell) $ such that every set of at least $ f(\ell) $ points in the plane contains $ \ell $ collinear points or an empty hexagon.

Keywords: empty hexagon

Toon Blast Cheats Generator 2024 Cheats Generator Tested On Android Ios (extra) ★★

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Toon Blast Cheats Generator 2024 Cheats Generator Tested On Android Ios (extra)

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Hamilton cycle in small d-diregular graphs ★★

Author(s): Jackson

An directed graph is $ k $-diregular if every vertex has indegree and outdegree at least $ k $.

Conjecture   For $ d >2 $, every $ d $-diregular oriented graph on at most $ 4d+1 $ vertices has a Hamilton cycle.

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Algebra ★★

Author(s):

Algebra

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Odd perfect numbers ★★★

Author(s): Ancient/folklore

Conjecture   There is no odd perfect number.

Keywords: perfect number

Matchington Mansion Stars Coins Cheats IOS And Android No Verification Generator 2024 (fresh method) ★★

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Matchington Mansion Stars Coins Cheats IOS And Android No Verification Generator 2024 (fresh method)

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

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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

Yu Gi Oh Duel Links Cheats Generator 2024 (safe and working) ★★

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Yu Gi Oh Duel Links Cheats Generator 2024 (safe and working)

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Shuffle-Exchange Conjecture (graph-theoretic form) ★★★

Author(s): Beneš; Folklore; Stone

Given integers $ k,n \ge 2 $, the 2-stage Shuffle-Exchange graph/network, denoted $ \text{SE}(k,n) $, is the simple $ k $-regular bipartite graph with the ordered pair $ (U,V) $ of linearly labeled parts $ U:=\{u_0,\dots,u_{t-1}\} $ and $ V:=\{v_0,\dots,v_{t-1}\} $, where $ t:=k^{n-1} $, such that vertices $ u_i $ and $ v_j $ are adjacent if and only if $ (j - ki) \text{ mod } t < k $ (see Fig.1).

Given integers $ k,n,r \ge 2 $, the $ r $-stage Shuffle-Exchange graph/network, denoted $ (\text{SE}(k,n))^{r-1} $, is the proper (i.e., respecting all the orders) concatenation of $ r-1 $ identical copies of $ \text{SE}(k,n) $ (see Fig.1).

Let $ r(k,n) $ be the smallest integer $ r\ge 2 $ such that the graph $ (\text{SE}(k,n))^{r-1} $ is rearrangeable.

Problem   Find $ r(k,n) $.
Conjecture   $ r(k,n)=2n-1 $.

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