Shifted primes with large prime power divisors

Shifted primes with large prime power divisors

We obtain significant lower bounds for the number of shifted prime numbers having a relatively large prime power divisor, where being large has various quantifications. For any given $k\geq 2$, our results show the existence of infinitely many prime numbers $p$ that lie over certain admissible arithmetic progressions, and of the form $p=q^ks+a$ for suitable positive integers $a$, where $q$ is prime and $s$ is forced to be genuinely small with respect to $p$. We prove the existence of such prime numbers over progressions both unconditionally, and then conditionally by either assuming the nonexistence of Siegel zeros or weaker forms of the Riemann hypothesis for Dirichlet $L$-functions. Our approach allows us to provide considerable uniformity regarding the size of the modulus of the progressions, where the sought primes belong to, and the shift parameter $a$ by restricting the size of $s$ at the same time. Finally, assuming the validity of a conjecture about the distribution of prime numbers along progressions with very large modulus, we demonstrate how it is possible to go beyond by showing that $s\leq (p-a)^{\epsilon}$ for every $\epsilon>0$ when $k=2$.

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  • [1] E. Alkan, Number of shifted primes as k-free integers, Proc. Journées Arithmétiques XXXI, De Gruyter Proceedings in Mathematics, Walter de Gruyter, Berlin, 15–34, 2022.
  • [2] A.I. Bonciocat, N.C. Bonciocat and A. Zaharescu On the irreducibility of polynomials that take a prime power value, Bull. Math. Soc. Sci. Math. Roumaine (N.S.) 54 (102), 41–54, 2011.
  • [3] H. Davenport, Multiplicative Number Theory, Third edition, Grad. Texts in Math., vol. 74, Springer-Verlag, New York, 2000.
  • [4] P.D.T.A. Elliot and H. Halberstam, A conjecture in prime number theory, Symposia Mathematica Vol. IV (INDAM Rome, 1968/1969) London, Academic Press, 59–72.
  • [5] G.H. Hardy and J.E. Littlewood, Contributions to the theory of the Riemann zetafunction and the theory of the distribution of primes, Acta Math. 41, 119–196, 1916.
  • [6] G.H. Hardy and J.E. Littlewood, Some problems of partitio numerorum: III. On the expression of a number as a sum of primes, Acta Math. 44, 1–70, 1923.
  • [7] G.H. Hardy and E.M. Wright, An introduction to the theory of numbers, Oxford University Press, Fifth edition, London, 1979.
  • [8] A. Languasco, On the sum of a prime and a k-free number, Funct. Approx. Comment. Math. 34, 19–26, 2005.
  • [9] W.H. Mills, A prime representing function, Bull. Amer. Math. Soc. 53, 604, 1947.
  • [10] K. Prachar, Primzahlverteilung, Springer-Verlag, Berlin-Göttingen-Heidelberg, 1957.
  • [11] K.A. Rodosskii, On the distribution of prime numbers in short arithmetic progressions, Izv. Akad. Nauk. USSR Ser. Mat. 12, 123–128, 1948.
  • [12] K.A. Rodosskii, On the zeros of Dirichlet L-functions, Izv. Akad. Nauk. USSR Ser. Mat. 13, 315–328, 1949.
  • [13] J.W. Sander, On numbers with a large prime power factor, Acta Math. Hungar. 63, 149–165, 1994.
  • [14] P. Sarnak and A. Zaharescu, Some remarks on the Landau-Siegel zeros, Duke Math. J. 111, 495–507, 2002.
  • [15] C.L. Siegel, Über die Classenzahl quadratischer Zahlkörper, Acta Arith. 1, 83–86, 1935.
  • [16] T. Tatuzawa, On the number of the primes in an arithmetic progression, Jap. J. Math. 21, 93–111, 1951.
  • [17] A. Walfisz, Zur Additive Zahlentheorie II, Math. Z. 40, 592–607, 1936.