A179875 - OEIS

A179875

Numbers h such that h and h+1 have same antiharmonic mean of the numbers k < h such that gcd(k, h) = 1.

1, 6, 10, 22, 46, 58, 65, 69, 77, 82, 106, 129, 166, 178, 185, 194, 210, 221, 226, 237, 254, 262, 265, 309, 321, 330, 346, 358, 365, 382, 398, 417, 437, 454, 462, 466, 469, 473, 478, 482, 493, 497, 502

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OFFSET

1,2

COMMENTS

Corresponding values of numbers h+1 see A179876.

Numbers h such that A175505(h) = A175505(h+1).

numbers h such that A175506(h) = A175506(h+1).

Antiharmonic mean B(h) of numbers k such that gcd(k, h) = 1 for numbers h >= 1 and k < h = A053818(n) / A023896(n) = A175505(h) / A175506(h).

Conjecture: also numbers k such that mu(k) = 1 and mu(k+1) = -1, where mu is the Möbius function (tested on the first 10^4 terms). - Amiram Eldar, Mar 06 2021

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

For n=3: a(3) = 10; B(10) = A175505(10) / A175506(10) = 7, B(11) = A175505(11) / A175506(11) = 7.

CROSSREFS

Cf. A179871, A179872, A179873, A179874, A179876, A179877, A179878, A179879, A179880, A179882, A179883, A179884, A179885, A179886, A179887, A179890, A179891.

Sequence in context: A063765 A085712 A337190 * A166305 A047651 A079426

Adjacent sequences: A179872 A179873 A179874 * A179876 A179877 A179878

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Jul 30 2010, Jul 31 2010

STATUS

approved