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The extension of the D(−k 2)-pair {k 2,k 2 + 1}

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Abstract

Let n be a nonzero integer. A set of m distinct positive integers is called a D(n)-m-tuple if the product of any two of them increased by n is a perfect square. Let k be a positive integer. In this paper, we show that if {k 2, k 2+1, c, d} is a D(−k 2)-quadruple with c < d, then c = 1 and d = 4k 2+1. This extends the work of the first author [20] and that of Dujella [4].

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References

  1. A. Baker and H. Davenport, The equations 3x 2 − 2 = y 2 and 8x 2 − 7 = z 2, Quart. J. Math. Oxford Ser. (2), 20 (1969), 129–137.

    Article  MathSciNet  MATH  Google Scholar 

  2. A. Dujella, Generalization of a problem of Diophantus, Acta Arith., 65 (1993), 15–27.

    MathSciNet  MATH  Google Scholar 

  3. A. Dujella, The problem of the extension of a parametric family of Diophantine triples, Publ. Math. Debrecen, 51 (1997), 311–322.

    MathSciNet  MATH  Google Scholar 

  4. A. Dujella, Complete solution of a family of simultaneous Pellian equations, Acta Math. Inform. Univ. Ostraviensis, 6 (1998), 59–67.

    MathSciNet  MATH  Google Scholar 

  5. A. Dujella, On the exceptional set in the problem of Diophantus and Davenport, Applications of Fibonacci Numbers, 7 (1998), 69–76.

    Article  MathSciNet  Google Scholar 

  6. A. Dujella, An extension of an old problem of Diophantus and Euler, Fibonacci Quart., 37 (1999), 312–314.

    MathSciNet  MATH  Google Scholar 

  7. A. Dujella, An absolute bound for the size of Diophantine m-tuples, J. Number Theory, 89 (2001), 126–150.

    Article  MathSciNet  MATH  Google Scholar 

  8. A. Dujella, An extension of an old problem of Diophantus and Euler. II, Fibonacci Quart., 40 (2002), 118–123.

    MathSciNet  MATH  Google Scholar 

  9. A. Dujella, There are only finitely many Diophantine quintuples, J. Reine Angew. Math., 566 (2004), 183–214.

    Article  MathSciNet  MATH  Google Scholar 

  10. A. Dujella, A. Filipin and C. Fuchs, Effective solution of the D(−1)-quadruple conjecture, Acta Arith., 128 (2007), 319–338.

    Article  MathSciNet  MATH  Google Scholar 

  11. A. Dujella and C. Fuchs, Complete solution of a problem of Diophantus and Euler, J. London Math. Soc., 71 (2005), 33–52.

    Article  MathSciNet  MATH  Google Scholar 

  12. A. Dujella and A. Pethő, A generalization of a theorem of Baker and Davenport, Quart. J. Math. Oxford (Ser. 2), 49 (1998), 291–306.

    MathSciNet  MATH  Google Scholar 

  13. A. Dujella and A. M. S. Ramasamy, Fibonacci numbers and sets with the property D(4), Bull. Belg. Math. Soc. Simon Stevin, 12 (2005), 401–412.

    MathSciNet  MATH  Google Scholar 

  14. A. Filipin, There does not exist a D(4)-sextuple, J. Number Theory, 128 (2008), 1555–1565.

    Article  MathSciNet  MATH  Google Scholar 

  15. A. Filipin and Y. Fujita, The D(-k 2)-triple {1, k 2+1, k 2+4} with k prime, Glas. Mat. Ser. III, 46 (2011), 311–323.

    Article  MathSciNet  MATH  Google Scholar 

  16. A. Filipin, B. He and A. Togbé, On the D(4)-triple {F 2k , F 2k+6, 4F 2k+4}, Fibonacci Quart., 48 (2010), 219–227.

    MathSciNet  MATH  Google Scholar 

  17. A. Filipin, B. He and A. Togbé, On a family of two-parametric D(4)-triples, Glas. Mat. Ser. III, to appear.

  18. Y. Fujita, The non-extensibility of D(4k)-triples {1, 4k(k − 1), 4k 2 + 1} with |k| prime, Glas. Mat. Ser. III, 41 (2006), 205–216.

    Article  MathSciNet  MATH  Google Scholar 

  19. Y. Fujita, The extensibility of Diophantine pairs {k−1, k+1}, J. Number Theory, 128 (2008), 322–353.

    Article  MathSciNet  MATH  Google Scholar 

  20. Y. Fujita, Extensions of the D(∓k 2)-triples {k 2, k 2 ± 1, 4k 2 ± 1}, Period. Math. Hungar., 59 (2009), 81–98.

    Article  MathSciNet  MATH  Google Scholar 

  21. Y. Fujita, The number of Diophantine quintuples, Glas. Mat. Ser. III, 45 (2010), 15–29.

    Article  MathSciNet  MATH  Google Scholar 

  22. B. He and A. Togbé, On a family of Diophantine triples {k,A 2 k +2A, (A+1)2 k + 2(A + 1)} with two parameters, Acta Math. Hungar., 124 (2009), 99–113.

    Article  MathSciNet  MATH  Google Scholar 

  23. B. He and A. Togbé, On a family of Diophantine triples {k,A 2 k +2A, (A+1)2 k + 2(A + 1)} with two parameters II, Period. Math. Hungar., 64 (2012), 1–10.

    Article  MathSciNet  MATH  Google Scholar 

  24. S. P. Mohanty and A. M. S. Ramasamy, The simultaneous Diophantine equations 5y 2 − 20 = x 2 and 2y 2 + 1 = z 2, J. Number Theory, 18 (1984), 356–359.

    Article  MathSciNet  MATH  Google Scholar 

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Correspondence to Yasutsugu Fujita.

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Communicated by Attila Pethő

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Fujita, Y., Togbé, A. The extension of the D(−k 2)-pair {k 2,k 2 + 1}. Period Math Hung 65, 75–81 (2012). https://doi.org/10.1007/s10998-012-2912-x

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  • DOI: https://doi.org/10.1007/s10998-012-2912-x

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