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A140577 Decimal expansion of Wroblewski's constant arising in nonaveraging sequences. 5
3, 0, 0, 8, 4, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A nonaveraging sequence contains no three terms which are in an arithmetic progression. Wroblewski (1984) showed that for infinite nonaveraging sequences Sup_{all nonaveraging sequences b(n)} Sum_{k>=1} 1/b(k) > 3.00849. [Typo corrected by Stefan Steinerberger, Aug 28 2008]

REFERENCES

S. R. Finch, "Erdos' Reciprocal Sum Constants." 2.20 in Mathematical Constants. Cambridge, England: Cambridge University Press, pp. 163-166, 2003.

R. K. Guy, "Nonaveraging Sets. Nondividing Sets." C16 in Unsolved Problems in Number Theory, 2nd ed. New York: Springer-Verlag, pp. 131-132, 1994.

LINKS

Table of n, a(n) for n=1..6.

Eric W. Weisstein, Nonaveraging Sequence.

J. Wroblewski, A Nonaveraging Set of Integers with a Large Sum of Reciprocals, Math. Comput. 43, 261-262, 1984.

Index entries related to non-averaging sequences

FORMULA

Decimal expansion of Sup_{all nonaveraging sequences b(n)} Sum_{k>=1} b(k).

CROSSREFS

Cf. A051013, A131741, A133234.

Sequence in context: A218538 A243163 A209490 * A068606 A106153 A166244

Adjacent sequences:  A140574 A140575 A140576 * A140578 A140579 A140580

KEYWORD

cons,more,nonn

AUTHOR

Jonathan Vos Post, Jul 05 2008

STATUS

approved

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Last modified October 15 11:03 EDT 2018. Contains 316224 sequences. (Running on oeis4.)