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%I #17 Mar 16 2019 17:00:39
%S 175742294,6263852385,16082297385,18625120185,32553626105,38947446285,
%T 37626449685,41194817265,103052922665,87988279533,103552755405,
%U 126755126589,131943742994,192245655405,226960409585,181521732405,502566224565,399451768365,403080683565,461943100905
%N Larger of reduced unitary amicable pair.
%C A pair m < n is a reduced unitary amicable pair if usigma(m) = usigma(n) = m + n + 1, where usigma(n) is the sum of unitary divisors of n (A034460). The terms are ordered according to their lesser counterparts (A306875).
%H Amiram Eldar, <a href="/A306876/b306876.txt">Table of n, a(n) for n = 1..28</a> (terms with lesser member below 10^12, from David Moews's site).
%H David Moews, <a href="http://djm.cc/amicable.html">Perfect, amicable and sociable numbers</a>
%H J. O. M. Pedersen, <a href="http://62.198.248.44/aliquot/tables.htm">Tables of Aliquot Cycles</a>
%e 175742294 is in the sequence since it is the larger of the amicable pair (172622505, 175742294): usigma(172622505) = usigma(175742294) = 348364800 = 172622505 + 175742294 + 1.
%t us[n_] := Times @@ (1 + Power @@@ FactorInteger[n]) - n; s={}; Do[m = us[n] - 1; If[m > n && us[m] == n + 1, AppendTo[s, m]], {n, 1, 10^9}]; s
%Y Cf. A003503, A002953, A126173, A034460, A306875.
%K nonn
%O 1,1
%A _Amiram Eldar_, Mar 14 2019
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