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For any triple of positive integers a = (a_1, a_2, a_3) the sequence of numbers the sequence g_i(a)_i=0^∞ is monotonically increasing with i, for i ≤ 14.

More generally, call a set of subgraphs of G a packing if the subgraphs are disjoint. Let f(G) be the number of packings of G by copies of a fixed graph K (so when K is an edge, this is the number of matchings). Does (5.3) hold when H…

Identify and characterise the product graphs whose curling numbers are the product of the curling numbers of their factors graphs.

There is no graph with uniform rank spread equal to two.

Every k-ary tangram T satisfies cut(T, R_k) ≤ d_k, for some finite constant d_k depending only on k.

The set reconstruction problem for multisets over commutative groupoids is an open problem, and it may be worth investigating.

Assume that p nmid (m-1) and 2 ≤ m ≤ q+1/3. Then the cliques from Proposition 4.6 and Proposition 4.7 are maximal.

Does there exist a graph with a constant neighbourhood of two independent vertices containing the maximal independent vertex sets V1 of cardinality k1 and V2 of cardinality k2 such that k1 ≠ k2 ?

From the above theorem, it seemed to suggest the following conjecture: if G_1 is m-extendable and G_2 is n-extendable (m, n ≥ 0), then their lexicographic product G_2 ∘ G_1 is (n+1)|V(G_1)|-factor-critical.

Specifically, we conjecture that similar processes will work for cycle pendant stars up to stars of size 15.

The generating function of the colored excedance on SD_n^D is log-concave for all n ≥ 1. The generating function of the absolute excedance on SD_n^D is log-concave for all n ≥ 10 and unimodal for all n ≥ 1.

For any uncovered set S of patterns, fracR_S,nn converges in distribution to a Bernoulli random variable Ber(p) for some p ∈ [0, 1]. If S contains a pattern starting with 1, then p = 1, and if S contains a pattern starting with its largest…

The set of two-pop-stack sortable permutations of length 2n+1 with exactly n ascents has an equal number of permutations with last block of size one as permutations with last block size greater than one. That is, a(2n+1, n) = 2b(2n+1, n)…

It is possible to adapt Theorem 1 to arbitrary posets (instead of 0, 1-posets) and to injective maps φ with x < y ⇔ φ(x) < φ(y) (instead of x ≤ y ⇔ φ(x) ≤ φ(y))?

What is the cop number of the flower snark J_n ?

For all k ≥ 0, the grid of size 3 × (2k+1) is an N-position for the game PUSH-CRAM. In addition, it is a bluff game.

For a simple example, consider the MINIMUM VERTEX COVER problem in fractionally treewidth-fragile graphs, or more generally in hereditary classes with sublinear separators. While the unweighted version can be dealt with by the local search…

Thus it remains to determine h_T(C_n) when n ≡ 1 or 2 (mod 3).

Take an n × n determinant such that its first column is the column of integers in the sequence of sequences S_i rectangular array and its first row is the k^th row, k=1,2,3,… . Then its determinant is given by (∏_j=1^n+1j^j-2)·( cn+k-1 n ).

Let r and q be integers such that 2 ≤ r ≤ 9 and r ≤ q. Then for all n ≥ r, the Turán graph T_r(n) has more q-colorings than any other graph with the same number of vertices and edges.