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A000173 Unitary-sociable numbers (smallest member of each cycle). 3

%I #18 Aug 30 2023 05:21:11

%S 30,1482,2418,24180,35238,263820,395730,473298,698130,763620,2212026,

%T 2233554,172459210,209524210,341354790,384121920,525150234,530946330,

%U 582129630,1799281330,2069510520,2514290520,3344596854,5251502340

%N Unitary-sociable numbers (smallest member of each cycle).

%C If n=product p_i^a_i, d=product p_i^c_i is a unitary divisor of n if each c_i is 0 or a_i.

%D R. K. Guy, Unsolved Problems in Number Theory, 3rd edition, Sect. B7.

%H Herman Jamke (hermanjamke(AT)fastmail.fm), Nov 01 2006, <a href="/A000173/b000173.txt">Table of n, a(n) for n = 1..44</a>

%H David Moews, <a href="http://djm.cc/amicable.html">Perfect, amicable and sociable numbers</a>.

%H J. O. M. Pedersen, <a href="http://amicable.homepage.dk/tables.htm">Tables of Aliquot Cycles</a>. [Broken link]

%H J. O. M. Pedersen, <a href="http://web.archive.org/web/20140502102524/http://amicable.homepage.dk/tables.htm">Tables of Aliquot Cycles</a>. [Via Internet Archive Wayback-Machine]

%H J. O. M. Pedersen, <a href="/A063990/a063990.pdf">Tables of Aliquot Cycles</a>. [Cached copy, pdf file only]

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SociableNumbers.html">Sociable Numbers</a>.

%Y Cf. A034444, A003416, A097323.

%K nonn,nice

%O 1,1

%A _N. J. A. Sloane_

%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Nov 01 2006

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Last modified April 24 05:36 EDT 2024. Contains 371918 sequences. (Running on oeis4.)