OFFSET
1,2
COMMENTS
From Bernd Mulansky, Jun 23 2021: (Start)
Additive bases: a(n) is the least integer k such that in each cyclic group Z_j with j>=k there is a subset of n elements all pairs (of distinct elements) of which add up to a different sum (in Z_j).
Such subsets are known as (modular) weak Sidon sets, weak B_2 sets, or well-spread sequences.
(End)
REFERENCES
Bela Bajnok, Additive Combinatorics: A Menu of Research Problems. Chapman & Hall/CRC, 2018. See Problem C.65.
A. Maturo and D. Yager-Elorriaga, Finding Sidon sets in abelian groups. Research Papers in Mathematics, B. Bajnok, ed., Gettysburg College, Vol. 7 (2008).
LINKS
Bela Bajnok, Additive Combinatorics: A Menu of Research Problems, arXiv:1705.07444 [math.NT], 2017. See Problem C.65 p. 166.
EXAMPLE
Z_j contains a weak Sidon set of size 8 for j=40 and for every j>=42, but not for j=41, hence a(8)=42.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Jul 06 2017
STATUS
approved