Random

Exponential Algorithms for Knapsack ★★

Author(s): Lipton

Conjecture  

The famous 0-1 Knapsack problem is: Given $ a_{1},a_{2},\dots,a_{n} $ and $ b $ integers, determine whether or not there are $ 0-1 $ values $ x_{1},x_{2},\dots,x_{n} $ so that $$ \sum_{i=1}^{n} a_{i}x_{i} = b.$$ The best known worst-case algorithm runs in time $ 2^{n/2} $ times a polynomial in $ n $. Is there an algorithm that runs in time $ 2^{n/3} $?

Keywords: Algorithm construction; Exponential-time algorithm; Knapsack

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:

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

Algorithm for graph homomorphisms ★★

Author(s): Fomin; Heggernes; Kratsch

Question  

Is there an algorithm that decides, for input graphs $ G $ and $ H $, whether there exists a homomorphism from $ G $ to $ H $ in time $ O(c^{|V(G)|+|V(H)|}) $ for some constant $ c $?

Keywords: algorithm; Exponential-time algorithm; homomorphism

3-Decomposition Conjectures ★★

Author(s):

Conjecture  

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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} $, $$\chi(G,p) \leq \frac{9}{8}\omega(G,p) + c $$

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

Author(s):

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

Keywords: cospectral; graph invariant; spectrum

Decomposing an even tournament in directed paths. ★★★

Author(s): Alspach; Mason; Pullman

Conjecture   Every tournament $ D $ on an even number of vertices can be decomposed into $ \sum_{v\in V}\max\{0,d^+(v)-d^-(v)\} $ directed paths.

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

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

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Dragon City Generator Cheats 2024 (generator!) ★★

Author(s):

Dragon City Generator Cheats 2024 (generator!)

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Latest Bingo Blitz Cheats Generator 999K Credits Free 2024 in 5 minutes (Up To) ★★

Author(s):

Latest Bingo Blitz Cheats Generator 999K Credits Free 2024 in 5 minutes (Up To)

Keywords:

Inequality of the means ★★★

Author(s):

Question   Is is possible to pack $ n^n $ rectangular $ n $-dimensional boxes each of which has side lengths $ a_1,a_2,\ldots,a_n $ inside an $ n $-dimensional cube with side length $ a_1 + a_2 + \ldots a_n $?

Keywords: arithmetic mean; geometric mean; Inequality; packing

Inequality for square summable complex series ★★

Author(s): Retkes

Conjecture   For all $ \alpha=(\alpha_1,\alpha_2,\ldots)\in l_2(\cal{C}) $ the following inequality holds $$\sum_{n\geq 1}|\alpha_n|^2\geq \frac{6}{\pi^2}\sum_{k\geq0}\bigg| \sum_{l\geq0}\frac{1}{l+1}\alpha_{2^k(2l+1)}\bigg|^2 $$

Keywords: Inequality

House Of Fun Cheats Generator 2024 for Android iOS (updated Generator) ★★

Author(s):

House Of Fun Cheats Generator 2024 for Android iOS (updated Generator)

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Complexity of the H-factor problem. ★★

Author(s): Kühn; Osthus

An $ H $-factor in a graph $ G $ is a set of vertex-disjoint copies of $ H $ covering all vertices of $ G $.

Problem  Let $ c $ be a fixed positive real number and $ H $ a fixed graph. Is it NP-hard to determine whether a graph $ G $ on $ n $ vertices and minimum degree $ cn $ contains and $ H $-factor?

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

Author(s):

Working My Singing Monsters Cheats Generator Online (No Survey)

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

Author(s):

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

Keywords:

The additive basis conjecture ★★★

Author(s): Jaeger; Linial; Payan; Tarsi

Conjecture   For every prime $ p $, there is a constant $ c(p) $ (possibly $ c(p)=p $) so that the union (as multisets) of any $ c(p) $ bases of the vector space $ ({\mathbb Z}_p)^n $ contains an additive basis.

Keywords: additive basis; matrix

Gta 5 Cheats Generator 2024 No Human Verification (Brand New) ★★

Author(s):

Gta 5 Cheats Generator 2024 No Human Verification (Brand New)

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Coin Master Spins Coins Cheats No Human Verification (Ios Android) ★★

Author(s):

Coin Master Spins Coins Cheats No Human Verification (Ios Android)

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

Author(s):

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

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

Author(s):

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

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Fixed-point logic with counting ★★

Author(s): Blass

Question   Can either of the following be expressed in fixed-point logic plus counting:
    \item Given a graph, does it have a perfect matching, i.e., a set $ M $ of edges such that every vertex is incident to exactly one edge from $ M $? \item Given a square matrix over a finite field (regarded as a structure in the natural way, as described in [BGS02]), what is its determinant?

Keywords: Capturing PTime; counting quantifiers; Fixed-point logic; FMT03-Bedlewo

Fasted Way! For Free Brawlhalla Cheats Generator Working 2024 Android Ios ★★

Author(s):

Fasted Way! For Free Brawlhalla Cheats Generator Working 2024 Android Ios

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Gta 5 Cheats Generator No Human Verification (Ios Android) ★★

Author(s):

Gta 5 Cheats Generator No Human Verification (Ios Android)

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Shuffle-Exchange Conjecture ★★★

Author(s): Beneš; Folklore; Stone

Given integers $ k,n\ge2 $, let $ d(k,n) $ be the smallest integer $ d\ge2 $ such that the symmetric group $ \frak S $ on the set of all words of length $ n $ over a $ k $-letter alphabet can be generated as $ \frak S = (\sigma \frak G)^d:=\sigma\frak G \sigma\frak G \dots \sigma\frak G $ ($ d $ times), where $ \sigma\in \frak S $ is the shuffle permutation defined by $ \sigma(x_1 x_2 \dots x_{n}) = x_2 \dots x_{n} x_1 $, and $ \frak G $ is the exchange group consisting of all permutations in $ \frak S $ preserving the first $ n-1 $ letters in the words.

Problem  (SE)   Evaluate $ d(k,n) $.
Conjecture  (SE)   $ d(k,n)=2n-1 $, for all $ k,n\ge2 $.

Keywords:

The 4x5 chessboard complex is the complement of a link, which link? ★★

Author(s): David Eppstein

Problem   Ian Agol and Matthias Goerner observed that the 4x5 chessboard complex is the complement of many distinct links in the 3-sphere. Their observation is non-constructive, as it uses the resolution of the Poincare Conjecture. Find specific links that have the 4x5 chessboard complex as their complement.

Keywords: knot theory, links, chessboard complex

FarmVille 2 Coins Farm Bucks Cheats in a few minutes new 2024 (No Survey) ★★

Author(s):

FarmVille 2 Coins Farm Bucks Cheats in a few minutes new 2024 (No Survey)

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Turán Problem for $10$-Cycles in the Hypercube ★★

Author(s): Erdos

Problem   Bound the extremal number of $ C_{10} $ in the hypercube.

Keywords: cycles; extremal combinatorics; hypercube

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

Author(s):

Bingo Blitz Cheats Generator Unlimited No Jailbreak (Premium)

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MONOPOLY GO Cheats Generator 2024 (fresh strategy) ★★

Author(s):

MONOPOLY GO Cheats Generator 2024 (fresh strategy)

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Sum of prime and semiprime conjecture ★★

Author(s): Geoffrey Marnell

Conjecture   Every even number greater than $ 10 $ can be represented as the sum of an odd prime number and an odd semiprime .

Keywords: prime; semiprime

Graceful Tree Conjecture ★★★

Author(s):

Conjecture   All trees are graceful

Keywords: combinatorics; graceful labeling

Real Racing 3 Cheats Generator in a few minutes new Cheats Generator 2024 (No Survey) ★★

Author(s):

Real Racing 3 Cheats Generator in a few minutes new Cheats Generator 2024 (No Survey)

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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

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

MONOPOLY GO Cheats Generator 2024 (Legal) ★★

Author(s):

MONOPOLY GO Cheats Generator 2024 (Legal)

Keywords:

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

"New Cheats" Subway Surfers Coins Keys Cheats Free 2024 ★★

Author(s):

"New Cheats" Subway Surfers Coins Keys Cheats Free 2024

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Fundamental group torsion for subsets of Euclidean 3-space ★★

Author(s): Ancient/folklore

Problem   Does there exist a subset of $ \mathbb R^3 $ such that its fundamental group has an element of finite order?

Keywords: subsets of euclidean space; torsion

Seagull problem ★★

Author(s):

Seagull problem

Keywords:

Negative association in uniform forests ★★

Author(s): Pemantle

Conjecture   Let $ G $ be a finite graph, let $ e,f \in E(G) $, and let $ F $ be the edge set of a forest chosen uniformly at random from all forests of $ G $. Then \[ {\mathbb P}(e \in F \mid f \in F}) \le {\mathbb P}(e \in F) \]

Keywords: forest; negative association

Rota's unimodal conjecture ★★★

Author(s): Rota

Let $ M $ be a matroid of rank $ r $, and for $ 0 \le i \le r $ let $ w_i $ be the number of closed sets of rank $ i $.

Conjecture   $ w_0,w_1,\ldots,w_r $ is unimodal.
Conjecture   $ w_0,w_1,\ldots,w_r $ is log-concave.

Keywords: flat; log-concave; matroid

Non-edges vs. feedback edge sets in digraphs ★★★

Author(s): Chudnovsky; Seymour; Sullivan

For any simple digraph $ G $, we let $ \gamma(G) $ be the number of unordered pairs of nonadjacent vertices (i.e. the number of non-edges), and $ \beta(G) $ be the size of the smallest feedback edge set.

Conjecture  If $ G $ is a simple digraph without directed cycles of length $ \le 3 $, then $ \beta(G) \le \frac{1}{2} \gamma(G) $.

Keywords: acyclic; digraph; feedback edge set; triangle free

Partial List Coloring ★★★

Author(s): Albertson; Grossman; Haas

Conjecture   Let $ G $ be a simple graph with $ n $ vertices and list chromatic number $ \chi_\ell(G) $. Suppose that $ 0\leq t\leq \chi_\ell $ and each vertex of $ G $ is assigned a list of $ t $ colors. Then at least $ \frac{tn}{\chi_\ell(G)} $ vertices of $ G $ can be colored from these lists.

Keywords: list assignment; list coloring

Lords Mobile Cheats Unlimited Gems Coins Generator (No Human Verification) ★★

Author(s):

Lords Mobile Cheats Unlimited Gems Coins Generator (No Human Verification)

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The Ultimate Guide to Gardenscapes Cheats and Hacks: Boost Your Game in 2024 ★★

Author(s):

Conjecture  

Keywords:

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

Quartic rationally derived polynomials ★★★

Author(s): Buchholz; MacDougall

Call a polynomial $ p \in {\mathbb Q}[x] $ rationally derived if all roots of $ p $ and the nonzero derivatives of $ p $ are rational.

Conjecture   There does not exist a quartic rationally derived polynomial $ p \in {\mathbb Q}[x] $ with four distinct roots.

Keywords: derivative; diophantine; elliptic; polynomial

Clash of Clans Gems Cheats without verification (Free) ★★

Author(s):

Clash of Clans Gems Cheats without verification (Free)

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