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A325177 Unitary highly touchable numbers: Numbers m > 1 such that a record number of numbers k have m as the sum of the proper unitary divisors of k. 1
2, 6, 8, 12, 22, 33, 49, 55, 67, 79, 91, 115, 121, 151, 169, 175, 181, 211, 295, 301, 361, 391, 421, 481, 511, 571, 631, 781, 841, 991, 1051, 1171, 1231, 1261, 1321, 1471, 1561, 1681, 1891, 2101, 2311, 2731, 3151, 3361, 3571, 3991, 4201, 4291, 4411, 4621, 5251 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The unitary version of A238895.

LINKS

Table of n, a(n) for n=1..51.

MATHEMATICA

us[1] = 0; us[n_] := Times @@ (1 + Power @@@ FactorInteger[n]) - n;  m = 300; v = Table[0, {m}]; Do[u = us[k]; If[2 <= u <= m, v[[u]]++], {k, 1, m^2}]; s = {}; vm = -1; Do[If[v[[k]] > vm, vm = v[[k]]; AppendTo[s, k]], {k, 2, m}]; s

CROSSREFS

Cf. A034448, A034460, A063948, A238895, A324938.

Sequence in context: A177869 A138639 A082473 * A263312 A226818 A113462

Adjacent sequences:  A325174 A325175 A325176 * A325178 A325179 A325180

KEYWORD

nonn

AUTHOR

Amiram Eldar, Sep 05 2019

STATUS

approved

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Last modified December 12 07:31 EST 2019. Contains 329948 sequences. (Running on oeis4.)