

A235057


The greedy sequence of real numbers at least 1 that do not contain any 6term geometric progressions with integer ratio.


0



1, 32, 64, 243, 288, 576, 729, 1152, 2048, 3645, 4000, 10240, 20736, 21952, 92160, 100000, 102400, 207360, 219520, 518400, 548800, 921600
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OFFSET

1,2


COMMENTS

The union of the halfopen intervals [a(2i1),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} with r an integer.


LINKS

Table of n, a(n) for n=1..22.
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 kterm geometric progressions for 3 <= k <= 9.
Sequence in context: A069492 A076469 A256819 * A249116 A110562 A275187
Adjacent sequences: A235054 A235055 A235056 * A235058 A235059 A235060


KEYWORD

nonn,more


AUTHOR

Kevin O'Bryant, Jan 03 2014


STATUS

approved



