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A286267 Totient highly abundant numbers: numbers n such that A092693(n)+n > A092693(m)+m for all m < n. 3
1, 2, 3, 4, 5, 7, 9, 11, 13, 17, 23, 29, 37, 41, 47, 53, 59, 67, 71, 73, 79, 83, 89, 97, 101, 107, 127, 131, 137, 149, 167, 179, 221, 223, 227, 233, 251, 257, 289, 317, 347, 353, 359, 383, 389, 431, 443, 449, 461, 467, 503, 557, 563, 569, 587, 641, 677, 697 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Analogous to A002093 (highly abundant numbers) as A082897 (perfect totient numbers) is analogous to A000396 (perfect numbers).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..1000

Paul Loomis and Florian Luca, On totient abundant numbers, Electronic Journal of Combinatorial Number Theory, Vol. 8, #A06 (2008).

MATHEMATICA

Function[s, Flatten[First@ Position[s, #] & /@ Union@ Rest@ FoldList[Max, 0, s]]]@ Table[(Total@ FixedPointList[EulerPhi, n] - 1), {n, 10^3}] (* Michael De Vlieger, May 06 2017 *)

CROSSREFS

Cf. A000396, A002093, A082897, A092693, A286265.

Sequence in context: A166684 A067126 A274197 * A008750 A076677 A029001

Adjacent sequences:  A286264 A286265 A286266 * A286268 A286269 A286270

KEYWORD

nonn

AUTHOR

Amiram Eldar, May 05 2017

STATUS

approved

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Last modified August 13 05:41 EDT 2020. Contains 336442 sequences. (Running on oeis4.)