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On extensions of mixed motives.

Christopher Deninger (1997)

Collectanea Mathematica

In this article we give an introduction to mixed motives and sketch a couple of ways to construct examples.

On extremal additive 𝔽 4 codes of length 10 to 18

Christine Bachoc, Philippe Gaborit (2000)

Journal de théorie des nombres de Bordeaux

In this paper we consider the extremal even self-dual 𝔽 4 -additive codes. We give a complete classification for length 10 . Under the hypothesis that at least two minimal words have the same support, we classify the codes of length 14 and we show that in length 18 such a code is equivalent to the unique 𝔽 4 -hermitian code with parameters [18,9,8]. We construct with the help of them some extremal 3 -modular lattices.

On extreme forms in dimension 8

Cordian Riener (2006)

Journal de Théorie des Nombres de Bordeaux

A theorem of Voronoi asserts that a lattice is extreme if and only if it is perfect and eutactic. Very recently the classification of the perfect forms in dimension  8 has been completed [5]. There are 10916 perfect lattices. Using methods of linear programming, we are able to identify those that are additionally eutactic. In lower dimensions almost all perfect lattices are also eutactic (for example 30 out of the 33 in dimension  7 ). This is no longer the case in dimension  8 : up to similarity, there...

On Fabry's gap theorem

Jan-Christoph Puchta (2002)

Archivum Mathematicum

By combining Turán’s proof of Fabry’s gap theorem with a gap theorem of P. Szüsz we obtain a gap theorem which is more general then both these theorems.

On families of 9-congruent elliptic curves

Tom Fisher (2015)

Acta Arithmetica

We compute equations for the families of elliptic curves 9-congruent to a given elliptic curve. We use these to find infinitely many non-trivial pairs of 9-congruent elliptic curves over ℚ, i.e. pairs of non-isogenous elliptic curves over ℚ whose 9-torsion subgroups are isomorphic as Galois modules.

On families of weakly dependent random variables

Tomasz Łuczak (2011)

Banach Center Publications

Let ( k ) be a family of random independent k-element subsets of [n] = 1,2,...,n and let ( ( k ) , ) = ( k ) ( ) denote a family of ℓ-element subsets of [n] such that the event that S belongs to ( k ) ( ) depends only on the edges of ( k ) contained in S. Then, the edges of ( k ) ( ) are ’weakly dependent’, say, the events that two given subsets S and T are in ( k ) ( ) are independent for vast majority of pairs S and T. In the paper we present some results on the structure of weakly dependent families of subsets obtained in this way. We also list...

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