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 A292983 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). 4
 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, 120, 160, 168, 210, 216, 240, 264, 312, 330, 360, 378, 384, 408, 456, 480, 600, 648, 672, 840, 1056, 1080, 1320, 1512, 1560, 1680, 1848, 1920, 2040, 2184, 2280, 2640 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Analogous to highly abundant numbers (A002093) with bi-unitary sigma (A188999) instead of sigma (A000203). LINKS Amiram Eldar, Table of n, a(n) for n = 1..569 (terms below 10^10) MATHEMATICA 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 *) CROSSREFS Cf. A002093, A188999, A285614. Sequence in context: A120370 A011866 A321152 * A174709 A008724 A287642 Adjacent sequences:  A292980 A292981 A292982 * A292984 A292985 A292986 KEYWORD nonn AUTHOR Amiram Eldar, Sep 27 2017 STATUS approved

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Last modified April 12 09:39 EDT 2021. Contains 342920 sequences. (Running on oeis4.)