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A140794 The smallest counterexample to the conjecture that the cardinality of the sumset is less than or equal to the cardinality of the difference set of every finite set of integers. 0
0, 2, 4, 7, 11, 12, 14 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A set with more sums than differences is called a MSTD set. Hegarty has constructed many such examples. Nathanson's abstract: This is a survey of open problems in different parts of combinatorial and additive number theory.

REFERENCES

P. V. Hegarty, Some explicit constructions of sets with more sums than differences, Acta Arith. 130(2007)61-77.

LINKS

Melvyn B. Nathanson, Problems in Additive Number Theory, III: Thematic Seminars at the Centre de Recerca Matematica, arXiv:0807.2073

EXAMPLE

Let A = {0, 2, 4, 7, 11, 12, 14}. Then the cardinality of the sumset, |A + A| = 26, while the cardinality of the difference set, |A - A| = 25.

CROSSREFS

Sequence in context: A134126 A091263 A101430 * A127575 A206853 A106265

Adjacent sequences:  A140791 A140792 A140793 * A140795 A140796 A140797

KEYWORD

fini,full,nonn

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), Jul 15 2008

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Last modified February 17 21:13 EST 2012. Contains 206085 sequences.