Initial day: July 31, 2001 　　　　 Last modified: May 27, 2013
　　　　　　
　 　 visits since April 10, 2002 　　　 　　　 　　　
 
　　　　　　

　　　　　　Zhi-Wei Sun
　　　　　　Department of Mathematics
　　　　　　Nanjing University
　　　　　　Nanjing 210093
　　　　　　People's Republic of China
　　　　　　E-mail: zwsun@nju.edu.cn
　　　　　　Office in the Dept.: Room 103
　　　　　　　　　　　　　　Last Name Sun
　　　　　　　　　　　　　　First Name Zhi Wei
　　　　　　　　　　　　　　Year of Birth 1965
Research Interests

　　　 Number Theory (especially Combinatorial Number Theory),
　　　 Combinatorics, Group Theory, Mathematical Logic.

Academic Service

　　　 Editor-in-Chief of Journal of Combinatorics and Number Theory, 2009--.
　　　　 You may submit your paper by sending the pdf file to zwsun@nju.edu.cn
　　　　 or to one of the two managing editors Florian Luca and Jiang Zeng. (A sample tex file)
　　　 Editorial Board Member of International Journal of Number Theory, 2009--.
　　　 Reviewer for Zentralblatt Math., 2007--.
　　　 Reviewer for Mathematical Reviews, 1992--.
　　　 Member of the American Mathematical Society, 1993--.
　　　 Referee for Proc. Amer. Math. Soc., Acta Arith., J. Number Theory, J. Combin. Theory Ser. A, European J. Combin.,
　　　　 Finite Fields Appl., Adv. in Appl. Math., Discrete Math., Discrete Appl. Math., Ramanujan J., SIAM Review etc.

School Education and Employment History

　　　1980.9--1983.7 The High Middle School Attached to Nanjing Normal Univ.
　　　1983.9--1992.6 Department of Mathematics, Nanjing University
　　　　　　　　　　 　 (Undergraduate--Ph. D. Candidate; B. Sc. 1987, Ph. D. 1992)
　　　1992.7-- 　　　 Teacher in Department of Mathematics, Nanjing University
　　　1994.4--1998.3 Associate Professor in Math.
　　　1998.4-- 　　　 Full Professor in Math.
　　　1999.11- 　　　 Supervisor of Ph. D. students

My Conjecture on Recurrence for Primes (see also Conj. 1.2 of this published paper)

　　 For any positive integer n different from 1,2,4,9, the (n+1)-th prime pn+1 is just the least positive integer m such that 2sk2 (k=1,...,n) are pairwise distinct modulo m, where sk = pk-pk-1+...+(-1)k-1p1. [I have verified this for n=1,...,100000.]

My Conjecture on Alternating Sums of Consecutive Primes (see also Conj. 1.3 of this published paper)

　　 For any positive integer m, there are consecutive primes pk,...,pn (k < n) not exceeding 2m+2.2*sqrt(m) such that m = pn-pn-1+...+(-1)n-kpk. [I have verified this for m up to 105.]

My Conjecture related to Bertrand's Postulate (see also A185636 and A204065 in OEIS)

Let n be any positive integer. Then, for some k=0,...n, both n+k and n+k2 are prime. [I have verified this conjecture for n up to 200,000,000.]

My Conjecture on Twin Primes and Sexy Primes

Every n=12,13,... can be written as p+q with p, p+6, 6q-1 and 6q+1 all prime. [I have verified this for n up to 1,000,000,000.]

My Conjecture involving Practical Numbers (see also A208244 and A209253 in OEIS)

Every positive integer n can be written as the sum of a practical number and a triangular number. Also, any odd number 2n-1 greater than one can be written as the sum of a Sophie Germain prime and a practical number. [I have verified both assertions for n up to 100,000,000.]

My Conjecture involving Primes Sandwiched between Twin Practical Numbers (see also A210480, A210681, A21165)

(i) Any integer n>3 can be written as p+q, where p is a prime with p-1 and p+1 both practical (i.e., {p-1,p,p+1} is a sandwich of the first kind), and q is either prime or practical. [This refines Goldbach's conjecture, and I have verified it for n up to 100,000,000.]

(ii) Each n=12,13,... can be written in the form (1+(n mod 2))p+q+r, where {p-1,p,p+1} and {q-1,q,q+1} are sandwiches of the first kind, and {r-1,r,r+1} is a sandwich of the second kind (i.e., r is a paractical number with r-1 and r+1 both prime). [I have verified this for n up to 3,000,000.]

(iii) Every integer n>5 can be expressed as the sum of a prime p with p-1 and p+1 both practical, a prime q with q+2 also prime, and a Fibonacci number. [I have verified this for n up to 2,000,000.]

My Curious Conjecture on Primes (see also A220272 in OEIS)

Any integer n>2 can be written as x2+y, where x and y are positive integers with 2xy-1 prime. In other words, for every n=3,4,... there is a prime in the form 2k(n-k2)-1 with k a positive integer. [I have verified this conjecture for n up to 3,000,000,000.]

My Conjecture on Prime Differences (see also arXiv:1211.1588 for more conjectures on primes)

Any integer n>7 can be written as p+q, where q is a positive integer, and p and 2pq+1 are primes. In general, for each m=0,1,2,..., any sufficiently large integer n can be written as x+y, where x and y are positive integers with x-m, x+m and 2xy+1 all prime. [I have verified the first assertion for n up to 1,000,000,000. The second assertion implies that for any positive even integer d there are infinitely many prime pairs {p,q} with p-q=d.]

My 100 Open Conjectures on Congruences

My 181 Conjectural Series for Powers of π and Other Constants (Announcements: 1, 2, 3, 4, 5, 6)

　　 Let C(n,k) denote the binomial coefficient n!/(k!(n-k)!) and let Tn(b,c) denote the coefficient of xn in (x2+bx+c)n. Then
　　　　 ∑k ≥ 0 (126k+31)Tk(22,212)3/(-80)3k = 880*sqrt(5)/(21π),
　　　　 ∑k ≥ 0 (24k+5)C(2k,k)Tk(4,9)2/282k = 49(sqrt(3)+sqrt(6))/(9π),
　　　　 ∑k ≥ 0(2800512k+435257)C(2k,k)Tk(73,576)2 /4342k = 10406669/(2sqrt(6)π),
　　　　 ∑k>0(28k2-18k+3)(-64)k /(k5C(2k,k)4C(3k,k)) = -14∑n>01/n3.
　　　　 ∑n ≥ 0(28n+5)24-2n C(2n,n)∑k ≥ 05k C(2k,k)2C(2(n-k),n-k)2/C(n,k) = 9(sqrt(2)+2)/π.
　　　　 ∑n ≥ 0(18n2+7n+1)(-128)-n ∑k ≥ 0C(-1/4,k)2C(-3/4,n-k)2 = 4*sqrt(2)/π2.
　　　　 ∑n ≥ 0(40n2+26n+5)(-256)-n ∑k ≥ 0C(n,k)2C(2k,k)C(2(n-k),n-k) = 24/π2.

My Hypothesis on the Parities of Ω(n)-n (see also a public message and arXiv:1204.6689)

　　 We have |{n ≤ x: n-Ω(n) is even}| > |{n ≤ x: n-Ω(n) is odd}| for any x ≥ 5, where Ω(n) denotes the total number of prime factors of n (counted with multiplicity). Moreover, ∑n ≤ x(-1)n-Ω(n) > sqrt(x) for any x ≥ 325. [I have shown that the hypothesis implies the Riemann Hypothesis, and verified it for x up to 1011.]

My Conjecture on Sums of Primes and Triangular Numbers

　　 Each natural number not equal to 216 can be written in the form p+Tx , where p is 0 or a prime, and Tx=x(x+1)/2 is a triangular number. [This has been verified up to 1,000,000,000,000.] In general, for any a,b=0,1,2,... and odd integer r, all sufficiently large integers can be written in the form 2ap +Tx , where p is either zero or a prime congruent to r modulo 2b.

My Conjecture on Sums of Polygonal Numbers

　　 For each integer m>2, any natural number n can be expressed as pm+1(x1) + pm+2(x2) + pm+3(x3) + r with x1,x2,x3 nonnegative integers and r among 0,...,m-3, where pk(x)=(k-2)x(x-1)/2+x (x=0,1,2,...) are k-gonal numbers. In particular, every natural number is the sum of a square, a pentagonal number and a hexagonal number. [For m=3, m=4,...,10, and m=11,...,40, this has been verified for n up to 30,000,000, 500,000 and 100,000 respectively.]

My Conjecture on Sums of Primes and Fibonacci Numbers

　　 Any integer n>4 can be represented as the sum of an odd prime and two or three positive Fibonacci numbers. [This has been verified up to 100,000,000,000,000.]

My Conjecture on Disjoint Cosets

　　 Let a1G1 , ..., akGk (k>1) be finitely many pairwise disjoint left cosets in a group G with all the indices [G:Gi] finite. Then, for some distinct i and j the greatest common divisor of [G:Gi] and [G:Gj] is at least k.

My Conjecture on Covers of Groups

　　 Let a1G1 , ..., akGk be finitely many left cosets in a group G which cover all the elements of G at least m>0 times with ajGj irredundant. Then k is at least m+f([G:Gj]), where f(1)=0 and f(p1 ... pr) =(p1-1) + ... +(pr-1) for any primes p1 , ..., pr .

My Conjecture on Linear Extension of the Erdos-Heilbronn Conjecture

Redmond-Sun Conjecture (in PlanetMath.)

Publications
　　　
　　　Papers Indexed in SCI or SCI-E Papers Listed by Field
　　　Recent Publications (2008-) Preprints on arXiv
　　　Publications during 2000-2007 Publications during 1987-1999
　　　
Other Information
　　　
　　　Research Grants Awards and Honours
　　　Academic Visits Courses Taught and Ph.D Students
　　　Notes on Some Conjectures of Z. W. Sun Introduction to Sun's Papers on Covers
　　　Books and Papers Citing Sun's Work Webpages of Wall-Sun-Sun Prime [1, 2, 3]
　　　Covers, Sumsets and Zero-sums Link to the useful Number Theory Web
　　　Mixed Sums of Primes and Other Terms Articles on arXiv: Combinatorics, Number Theory
　　　
Invited Lectures in Mathematics
  1. Simple Ideas for Famous Problems, 1996.
  2. Various Number-theoretic Quotients and Related Congruences, 2000.
  3. Recent Progress on Covers of the Integers and Their Applications, 2000.
  4. On Hilbert's Tenth Problem and Related Topics, 2000.
  5. Recent Progress on Combinatorial Number Theory (Chinese), 2001.
  6. Equalities and Inequalities Related to Covers of Z or Groups, 2002.
  7. On the Structure of Periodic Arithmetical Maps, 2002.
  8. New Results on Subset Sums, 2002.
  9. On Zero-sum Problems, 2002.
  10. On the Sum $\sum_{k\equiv r (mod m)}\binom nk$ and Related Results, 2002.
  11. Introduction to Bernoulli and Euler Polynomials, 2002.
  12. Problems and Results in Combinatorial Number Theory, 2002.
  13. Sumsets with Polynomial Restrictions, 2002.
  14. The Magic of Mathematics (Chinese), 2002, 2006.
  15. How to Unify Covering Systems, Restricted Sumsets and Zero-sum Problems, 2003.
  16. Recent Progress on Zero-sum Problems and Snevily's Conjecture, 2004.
  17. Covering Systems and their Connections to Zero-sums, 2004.
  18. On Disjoint Systems of Residue Classes or Cosets of Subgroups, 2004.
  19. On Various Combinatorial Sums and Related Identities, 2004.
  20. Two Local-Global Theorems and a Powerful Formula, 2004.
  21. Groups and Combinatorial Number Theory, 2004.
  22. On Some Conjectures of Erdos-Heilbronn, Lev and Snevily, 2004, 2005.
  23. Problems and Results on Covering Systems, 2005.
  24. Some Congruences Motivated by Algebraic Topology, 2005.
  25. Some Curious Results on Bernoulli and Euler Polynomials, 2005, 2006.
  26. A Survey of Zero-sum Problems on Abelian Groups, 2006.
  27. Recent Progress on Congruences involving Binomial Coefficients, 2006.
  28. Covering Systems and Periodic Arithmetical Functions, 2006.
  29. Combinatorial Aspects of Covers of Groups by Cosets or Subgroups, 2006.
  30. Curious Identities and Congruences involving Bernoulli Polynomials, 2006.
  31. Combinatorial Aspects of Szemeredi's Theorem, 2007.
  32. Additive Combinatorics and Latin Transversals, 2007.
  33. Sums of Squares and Triangular Numbers, and Rado Numbers for Linear Equations, 2007.
  34. An Additive Theorem Related to Latin Transversals, 2007.
  35. Some Famous Problems and Related Results in Combinatorial Number Theory, 2007.
  36. Groups in Combinatorial Number Theory, 2007.
  37. Various Extensions of Some Basic Results in Combinatorial Number Theory, 2008.
  38. Recent Problems and Results Involving Binomial Coefficients, 2008.
  39. An Extremal Problem on Covers of Abelian Groups, 2008.
  40. Study Covers of Groups via Characters and Number Theory, 2008.
  41. On Representations of Integers Involving Triangular Numbers, 2008.
  42. Some New Conjectures Involving Primes, 2009.
  43. Problems and Results in Additive Combinatorics, 2009.
  44. Polygonal Numbers, Primes and Ternary Quadratic Forms, 2009.
  45. Combinatorial Number Theory in China, 2009.
  46. On the DKSS Technique and the DKSS Conjecture, 2010.
  47. Some Sophisticated Applications of the Combinatorial Nullstellensatz, 2010.
  48. Conjectures and Results on Super Congruences, 2010.
  49. Conjectures for Super Congruences and Series for π and Other Constants (45 minutes version), 2010.
  50. Conjectures for Super Congruences and Series for π and Other Constants (30 minutes version), 2010.
  51. Super Congruences involving Binomial Coefficients and New Series for some Famous Constants, 2010.
  52. Arithmetic Properties of Combinatorial Quantities, 2010.
  53. On Divisibility concerning Binomial Coefficients, 2010.
  54. Correspondence between Series and Congruences, 2010.
  55. On Weighted Extension of the Erdos-Heilbronn Conjecture, 2011.
  56. On the DKSS Conjecture for Finite Abelian Groups, 2011.
  57. Number Theory behind Series for Powers of π, 2011.
  58. Conjectures and Results on x2 mod p2 with 4p=x2+dy2, 2011.
  59. Combinatorial Congruences via the Zeilberger Algorithm, 2011.
  60. On Arithmetic Properties of Bell Numbers, Delannoy Numbers and Schroder Numbers, 2011.
  61. Conjectures and Results on Generalized Trinomial Coefficients and Motzkin Numbers, 2011.
  62. Some Sophisticated Congruences involving Fibonacci Numbers, 2011.
  63. Some of my Number-theoretic Conjectures and related Progress, 2011.
  64. Historical Remarks on my Conjectural Congruences and Series for 1/π, 2011.
  65. Primes from the Viewpoint of Combinatorics, 2012.
  66. p-adic Congruences Motivated by Series, 2012.
  67. Various New Observations about Primes, 2012.
  68. Conjectures involving Arithmetical Sequences, 2012.
  69. The Riddle of Primes, 2012.
  70. Apery Numbers, Franel Numbers and Binary Quadratic Forms, 2013.
  71. Some New Representation Problems involving Primes, 2013.
Selected Photographs
  1. at Venice (Venezia), Florence (Firenze), Genova, Rome (Roma), Trieste (2004)
  2. at Vienna (Wien), Graz (2004), Lyon, Bordeaux, Pacific beach (2005), Osaka (2008)
  3. at MIT [1,2] and University of California at Irvine [1,2,3] (2006)
  4. at Univ. of Wisconsin at Madison and Univ. of Illinois at Urbana Champaign (2006)
  5. at Stanford University [1, 2, 3, 4, 5] (2010)
  6. with Prof. M. Agrawal (famous for the AKS primality test) at ICTP, Trieste (2004)
  7. with Prof. R. Schoof (famous for Schoof's algorithm) at Rome (2004)
  8. with Prof. A. Perelli at Genova (2004)
  9. with Prof. A. Geroldinger and his wife at Graz (2004)
  10. with Prof. R. Sprugnoli, D. Merlini and D. G. Rogers at Florence (2004)
  11. with Prof. R. P. Stanley, R. A. Askey and J. Zeng at Tianjin (2004)
  12. with Prof. Y. Bilu at Bordeaux (2005)
  13. with Prof. J. Zeng and Prof. J. L. Nicolas at Institute of Camille Jordan (2005)
  14. Photographs at the Integers Conference 2005 (West Georgia Univ., Oct. 27-30):
    Prof. R. L. Graham, the Graham couple, Prof. C. Pomerance,
    Prof. M. B. Nathanson, Prof. Fan Chung and M. B. Nathanson, Prof. B. Landman;
    with Prof. R.L. Graham and Fan Chung, C. Pomerance and S. Wagstaff,
    with Prof. M. B. Nathanson, H. Diamond and D. Goldston, B. Landman, S. Milne,
    with Prof. A. Bialostocki, T. Brown, K. O'Bryant and R. L. Jin, V. F. Lev.
  15. with Prof. R. Askey, K. Ono and T. H. Yang at Univ. of Wisconsin at Madison (2006)
  16. with Prof. H. Halberstam and P. T. Bateman at UI Urbana-Champaign (2006)
  17. with Prof. R. P. Stanley at MIT (Massachusetts Institute of Technology) (2006),
    with Prof. B. Green (famous for the Green-Tao theorem) at his MIT office (2006)
  18. with Prof. K. Rubin and D. Wan at Univ. of California at Irvine (2006)
  19. with Prof. B. Berndt at Nanjing University (2006)
  20. with Prof. A. Schinzel at Weihai (Shandong Province, China) (2006)
  21. with Prof. W. Konen at Osaka (Japan) (2008)
  22. with Prof. R. Schoof and Z. H. Sun in Xuanwu Park at Nanjing (2008)
  23. with Prof. M. Waldschmidt in India (2010)
  24. with Prof. S. D. Adhikari and Dr. D. J. Grynkiewicz in India (2010)
  25. with Prof. Wen-Ching Li, Don Zagier and his wife in Taiwan (2010)
  26. Pictures at the 1st Workshop on Number Theory, Combinatorics and their Interactions (Nanjing Univ., August 10-12, 2007):
    A Collective Photograph of Participants, Prof. Wen-Ching Winnie Li [1, 2, 3];
    Prof. Qin Yue, Zhi-Wei Sun, Keqin Feng, Wen-Ching W. Li, Daqing Wan and Yong-Gao Chen;
    W. C. Li, Z. W. Sun and D. Wan, W. C. Li and Z. W. Sun, W. C. Li and D. Wan.
　　 Curriculum Vitae of Zhi-Wei Sun
　　　　
　Zhi-Wei Sun has the copyright of those unpublished materials at this website.
　　　 The copyright of each published or accepted paper is held by the corresponding publisher.