The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A327469 Number of nonempty subsets of [1..n] which are geometric progressions of length >= 3 with rational ratio and are locally maximal. 2
 0, 0, 0, 1, 1, 1, 1, 1, 3, 3, 3, 4, 4, 4, 4, 5, 5, 7, 7, 8, 8, 8, 8, 8, 12, 12, 12, 13, 13, 13, 13, 14, 14, 14, 14, 19, 19, 19, 19, 19, 19, 19, 19, 20, 22, 22, 22, 23, 29, 33, 33, 34, 34, 34, 34, 34, 34, 34, 34, 35, 35, 35, 37, 40, 40, 40, 40, 41, 41, 41, 41, 45, 45, 45, 49, 50, 50, 50, 50, 51, 55, 55, 55, 56, 56, 56, 56, 56, 56, 58, 58, 59, 59, 59, 59, 60, 60, 66, 68, 77 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,9 COMMENTS Exceptionally, DATA section give first 100 terms. One might have expected that the GP would be required to have an integer ratio, but in fact we allow rational ratios. The GPs can be assumed to be increasing. LINKS Table of n, a(n) for n=1..100. CROSSREFS Cf. A309095, A327466. Sequence in context: A134849 A096056 A050501 * A105590 A220845 A361469 Adjacent sequences: A327466 A327467 A327468 * A327470 A327471 A327472 KEYWORD nonn AUTHOR N. J. A. Sloane, Oct 03 2019, using data computed by Rob Pratt. STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 8 08:19 EDT 2023. Contains 363157 sequences. (Running on oeis4.)