For any simple digraph , we let be the number of unordered pairs of nonadjacent vertices (i.e. the number of non-edges), and be the size of the smallest feedback edge set.
Conjecture If is a simple digraph without directed cycles of length , then .
Conjecture Define a array of positive integers where the first row consists of some distinct positive integers arranged in increasing order, and the second row consists of any positive integers in any order. Create a new array where the first row consists of all the integers that occur in the first array, arranged in increasing order, and the second row consists of their multiplicities. Repeat the process. For example, starting with the array , the sequence is: -> -> -> -> -> -> -> -> -> -> -> , and we now have a fixed point (loop of one array).
The process always results in a loop of 1, 2, or 3 arrays.
Conjecture Polignac's Conjecture: For any positive even number n, there are infinitely many prime gaps of size n. In other words: There are infinitely many cases of two consecutive prime numbers with difference n.
In particular, this implies:
Conjecture Twin Prime Conjecture: There are an infinite number of twin primes.
A covering design, or covering, is a family of -subsets, called blocks, chosen from a -set, such that each -subset is contained in at least one of the blocks. The number of blocks is the covering’s size, and the minimum size of such a covering is denoted by .
Problem Find a closed form, recurrence, or better bounds for . Find a procedure for constructing minimal coverings.
Conjecture If a finite set of unit balls in is rearranged so that the distance between each pair of centers does not decrease, then the volume of the union of the balls does not decrease.
Conjecture \item If is a countable connected graph then its third power is hamiltonian. \item If is a 2-connected countable graph then its square is hamiltonian.
Problem Let and be two -uniform hypergraph on the same vertex set . Does there always exist a partition of into classes such that for both , at least hyperedges of meet each of the classes ?
Conjecture Let and . Then for any neighborhood there is such that is periodic point of
There is an analogous conjecture for flows ( vector fields . In the case of diffeos this was proved by Charles Pugh for . In the case of Flows this has been solved by Sushei Hayahshy for . But in the two cases the problem is wide open for
Begin with the generating function for unrestricted partitions:
(1+x+x^2+...)(1+x^2+x^4+...)(1+x^3+x^6+...)...
Now change some of the plus signs to minus signs. The resulting series will have coefficients congruent, mod 2, to the coefficients of the generating series for unrestricted partitions. I conjecture that the signs may be chosen such that all the coefficients of the series are either 1, -1, or zero.
Conjecture Is the approximation ratio for the Maximum Edge Disjoint Paths (MaxEDP) or the Maximum Integer Multiflow problem (MaxIMF) bounded by a constant in -outerplanar graphs or tree-width graphs?
Conjecture Let is a -separable (the same as for symmetric transitive) compact funcoid and is a uniform space (reflexive, symmetric, and transitive endoreloid) such that . Then .
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 be a -separable compact reflexive symmetric funcoid and be a reloid such that \item ; \item .
Conjecture Let be a sequence of points in with the property that for every , the points are distinct, lie on a unique sphere, and further, is the center of this sphere. If this sequence is periodic, must its period be ?
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, we let 
be the number of unordered pairs of nonadjacent vertices (i.e. the number of non-edges), and 
be the size of the smallest 
, then 
. 
, what is the smallest integer 
such that 
? 
array of positive integers where the first row consists of some distinct positive integers arranged in increasing order, and the second row consists of any positive integers in any order. Create a new array where the first row consists of all the integers that occur in the first array, arranged in increasing order, and the second row consists of their multiplicities. Repeat the process. For example, starting with the array ![$ [1; 1] $](/files/tex/73f8649de444361674c157a2fe98e0c5783f1c46.png)
, the sequence is: ![$ [1; 2] $](/files/tex/83c3d9d7589f716ed6b0f05d26d36dabe8ba47aa.png)
-> ![$ [1, 2; 1, 1] $](/files/tex/a6a696aec4e84df6bc046cf6d30a4df80e156a14.png)
-> ![$ [1, 2; 3, 1] $](/files/tex/98b2f3e4134422c8a286f0326fc2f57ca9be2ab7.png)
-> ![$ [1, 2, 3; 2, 1, 1] $](/files/tex/19a9d24510f4551fa45b950aed32efed0636b355.png)
-> ![$ [1, 2, 3; 3, 2, 1] $](/files/tex/b00d573110ba8c2472820409103dd4cbd7bff7cc.png)
-> ![$ [1, 2, 3; 2, 2, 2] $](/files/tex/2aae90b65ae3f116402a1c0143127f80d86acdf0.png)
-> ![$ [1, 2, 3; 1, 4, 1] $](/files/tex/d614399c4078a70fbffb24eb99816a0974423175.png)
-> ![$ [1, 2, 3, 4; 3, 1, 1, 1] $](/files/tex/bf4dd82eaf95bd71a88cb78d3367efa2c7e4c942.png)
-> ![$ [1, 2, 3, 4; 4, 1, 2, 1] $](/files/tex/a4ef5900a9dde9b32311afe7dee2b143f42c405f.png)
-> ![$ [1, 2, 3, 4; 3, 2, 1, 2] $](/files/tex/ff367376ed7bb74fc6207273d7157062b83a1be6.png)
-> ![$ [1, 2, 3, 4; 2, 3, 2, 1] $](/files/tex/81ba2b3608ddba2fc95d32b74b70279f3f5adc5b.png)
, and we now have a fixed point (loop of one array).
is an invertible 
matrix, then there is an 
of ![$ [A A] $](/files/tex/d1e9d82c656535b507686183e640178057fae455.png)
so that 
is nonzero. 
-connected planar graph, then 
has a Hamilton cycle. 
denote the 
satisfies 
. 
covering design, or covering, is a family of 
-subsets, called blocks, chosen from a 
-set, such that each 
-subset is contained in at least one of the blocks. The number of blocks is the covering’s size, and the minimum size of such a covering is denoted by 
.
. Find a procedure for constructing minimal coverings. 
is rearranged so that the distance between each pair of centers does not decrease, then the volume of the union of the balls does not decrease. 
-graph if it has a bipartition 
so that every vertex in 
and every vertex in 
. 
denote the 
? 
there is an integer 
such that every set of at least 
collinear points or an empty hexagon. 
and 
be two 
-uniform hypergraph on the same vertex set 
. Does there always exist a partition of 
such that for both 
, at least 
hyperedges of 
meet each of the classes 
and 
. Then for any neighborhood 
there is 
such that 
is periodic point of 
vector fields . In the case of diffeos this was proved by Charles Pugh for 
. In the case of Flows this has been solved by Sushei Hayahshy for 
satisfy 
. Then the elements of 
and 
so that the sums 
are pairwise distinct. 
be a digraph all of whose strong components are nontrivial. Then 
. 
be an integer and let 
be a minor minimal 
. Then either 
minor for some 
or 
is a 
-separable (the same as 
for symmetric transitive) compact funcoid and 
. Then 
. 
. 
. 
be a sequence of points in 
with the property that for every 
, the points 
are distinct, lie on a unique sphere, and further, 
is the center of this sphere. If this sequence is periodic, must its period be 
? 
in the hypercube. 
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