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 100 Open Conjectures on Congruences
My 170 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
(221k+28)C(2k,k)Tk(6,2)2/450k
= 2700/(7π),
∑k ≥ 0(450296k+53323)C(2k,k)Tk(171,-171)2
/(-5177196)k
= 113535*sqrt(7)/(2π).
See all the 58 such conjectural series for 1/π.
∑k>0(10k-3)8k
/(k3C(2k,k)2C(3k,k))
= π2/2,
∑k>0(35k-8)81k
/(k3C(2k,k)2C(4k,2k))
= 12π2.
∑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 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.)
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