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A235059 The greedy sequence of real numbers at least 1 that do not contain any 8-term geometric progressions with integer ratio. 0
1, 128, 256, 2304, 3456, 16384, 32768, 163840, 288000, 331776, 497664, 884736, 995328 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The union of the half-open intervals [a(2i-1),a(2i)) is the greedy set of real numbers at least 1 that does not contain any subset of the form {a, ar, ar^2, ar^3, ar^4, ar^5, ar^6, ar^7} with r an integer.

LINKS

Table of n, a(n) for n=1..13.

M. B. Nathanson, K. O'Bryant, A problem of Rankin on sets without geometric progressions, arXiv preprint arXiv:1408.2880, 2014

CROSSREFS

A235054 through A235060 give the greedy sets avoiding k-term geometric progressions for 3 <= k <= 9.

Sequence in context: A255997 A256821 A172421 * A045053 A234877 A229360

Adjacent sequences:  A235056 A235057 A235058 * A235060 A235061 A235062

KEYWORD

nonn,more

AUTHOR

Kevin O'Bryant, Jan 03 2014

STATUS

approved

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Last modified December 9 08:41 EST 2021. Contains 349627 sequences. (Running on oeis4.)