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Diophantine m -tuples and elliptic curves

Andrej Dujella (2001)

Journal de théorie des nombres de Bordeaux

A Diophantine m -tuple is a set of m positive integers such that the product of any two of them is one less than a perfect square. In this paper we study some properties of elliptic curves of the form y 2 = ( a x + 1 ) ( b x + 1 ) ( c x + 1 ) , where { a , b , c } , is a Diophantine triple. In particular, we consider the elliptic curve E k defined by the equation y 2 = ( F 2 k x + 1 ) ( F 2 k + 2 x + 1 ) ( F 2 k + 4 x + 1 ) , where k 2 and F n , denotes the n -th Fibonacci number. We prove that if the rank of E k ( 𝐐 ) is equal to one, or k 50 , then all integer points on E k are given by ( x , y ) { ( 0 ± 1 ) , ( 4 F 2 k + 1 F 2 k + 2 F 2 k + 3 ± 2 F 2 k + 1 F 2 k + 2 - 1 × 2 F 2 k + 2 2 + 1 2 F 2 k + 2 F 2 k + 3 + 1 } .

Diophantine Undecidability of Holomorphy Rings of Function Fields of Characteristic 0

Laurent Moret-Bailly, Alexandra Shlapentokh (2009)

Annales de l’institut Fourier

Let K be a one-variable function field over a field of constants of characteristic 0. Let R be a holomorphy subring of K , not equal to K . We prove the following undecidability results for R : if K is recursive, then Hilbert’s Tenth Problem is undecidable in R . In general, there exist x 1 , ... , x n R such that there is no algorithm to tell whether a polynomial equation with coefficients in ( x 1 , ... , x n ) has solutions in R .

Distribution of Mordell-Weil ranks of families of elliptic curves

Bartosz Naskręcki (2016)

Banach Center Publications

We discuss the distribution of Mordell-Weil ranks of the family of elliptic curves y² = (x + αf²)(x + βbg²)(x + γh²) where f,g,h are coprime polynomials that parametrize the projective smooth conic a² + b² = c² and α,β,γ are elements from ℚ̅. In our previous papers we discussed certain special cases of this problem and in this article we complete the picture by proving the general results.

Elliptic curves associated with simplest quartic fields

Sylvain Duquesne (2007)

Journal de Théorie des Nombres de Bordeaux

We are studying the infinite family of elliptic curves associated with simplest cubic fields. If the rank of such curves is 1, we determine the whole structure of the Mordell-Weil group and find all integral points on the original model of the curve. Note however, that we are not able to find them on the Weierstrass model if the parameter is even. We have also obtained similar results for an infinite subfamily of curves of rank 2. To our knowledge, this is the first time that so much information...

Elliptic curves over function fields with a large set of integral points

Ricardo P. Conceição (2013)

Acta Arithmetica

We construct isotrivial and non-isotrivial elliptic curves over q ( t ) with an arbitrarily large set of separable integral points. As an application of this construction, we prove that there are isotrivial log-general type varieties over q ( t ) with a Zariski dense set of separable integral points. This provides a counterexample to a natural translation of the Lang-Vojta conjecture to the function field setting. We also show that our main result provides examples of elliptic curves with an explicit and arbitrarily...

Elliptic curves with ( [ 3 ] ) = ( ζ 3 ) and counterexamples to local-global divisibility by 9

Laura Paladino (2010)

Journal de Théorie des Nombres de Bordeaux

We give a family h , β of elliptic curves, depending on two nonzero rational parameters β and h , such that the following statement holds: let be an elliptic curve and let [ 3 ] be its 3-torsion subgroup. This group verifies ( [ 3 ] ) = ( ζ 3 ) if and only if belongs to h , β .Furthermore, we consider the problem of the local-global divisibility by 9 for points of elliptic curves. The number 9 is one of the few exceptional powers of primes, for which an answer to the local-global divisibility is unknown in the case of such...

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