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%I #11 Jan 21 2020 10:23:03
%S 1,2,3,4,5,6,8,10,12,14,16,18,21,22,24,30,40,42,48,54,66,72,78,88,96,
%T 120,160,168,210,216,240,264,312,330,360,378,384,408,456,480,600,648,
%U 672,840,1056,1080,1320,1512,1560,1680,1848,1920,2040,2184,2280,2640
%N Bi-unitary highly abundant numbers: numbers n such that bsigma(n) > bsigma(m) for all m < n, where bsigma is the sum of the bi-unitary divisors function (A188999).
%C Analogous to highly abundant numbers (A002093) with bi-unitary sigma (A188999) instead of sigma (A000203).
%H Amiram Eldar, <a href="/A292983/b292983.txt">Table of n, a(n) for n = 1..569</a> (terms below 10^10)
%t f[n_] := Select[Divisors[n], Function[d, CoprimeQ[d, n/d]]]; bsigma[m_] := DivisorSum[m, # &, Last@Intersection[f@#, f[m/#]] == 1 &]; a = {}; bmax = 0; Do[b = bsigma[n]; If[b > bmax, AppendTo[a, n]; bmax = b], {n, 3000}]; a (* after _Michael De Vlieger_ at A188999 *)
%Y Cf. A002093, A188999, A285614.
%K nonn
%O 1,2
%A _Amiram Eldar_, Sep 27 2017
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