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A060021
Maximal size of a subset of any Abelian group of order n that does not contain 0 and fails to span the group nontrivially.
1
1, 1, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 7, 6, 8, 7, 9, 7, 10, 8, 11, 8, 12, 9, 13, 9, 14, 9, 15, 11, 16, 10, 17, 10, 18, 13, 19, 11, 20, 11, 21, 15, 22, 12, 23
OFFSET
2,3
REFERENCES
J. R. Griggs (griggs(AT)math.sc.edu), personal communication, Apr 24, 2001.
LINKS
J. R. Griggs, Spanning subset sums for finite Abelian groups, Discrete Math., 229 (2001), 89-99.
FORMULA
a(2n) = n - 1 for n >= 10 [from Griggs]. - Sean A. Irvine, Oct 22 2022
a(p) = floor(2*sqrt(p-2)) - 1 for prime p >= 3 [from Griggs]. - Sean A. Irvine, Oct 22 2022
CROSSREFS
Cf. A060020.
Sequence in context: A084500 A084557 A024417 * A350029 A000006 A061017
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Mar 17 2001
EXTENSIONS
a(21)-a(48) from Sean A. Irvine, Oct 22 2022
STATUS
approved