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A327945 Nonunitary pseudoperfect numbers: numbers that equal to the sum of a subset of their nonunitary divisors. 5
24, 36, 48, 72, 80, 96, 108, 112, 120, 144, 160, 168, 180, 192, 200, 216, 224, 240, 252, 264, 288, 300, 312, 320, 324, 336, 352, 360, 384, 392, 396, 400, 408, 416, 432, 448, 456, 468, 480, 504, 528, 540, 552, 560, 576, 588, 600, 612, 624, 640, 648, 672, 684 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The nonunitary version of A005835.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

36 is in the sequence since its nonunitary divisors are 2, 3, 6, 12, 18 and 36 = 6 + 12 + 18.

MATHEMATICA

nudiv[n_] := Module[{d = Divisors[n]}, Select[d, GCD[#, n/#] > 1 &]]; s = {}; Do[d = nudiv[n]; If[Total[d] < n, Continue[]]; c = SeriesCoefficient[Series[Product[1 + x^d[[i]], {i, Length[d]}], {x, 0, n}], n]; If[c > 0, AppendTo[s, n]], {n, 1, 700}]; s

CROSSREFS

Supersequence of A064591.

Cf. A005835, A064597, A293188, A292985, A306983.

Sequence in context: A067766 A306776 A300794 * A078347 A187516 A165602

Adjacent sequences:  A327942 A327943 A327944 * A327946 A327947 A327948

KEYWORD

nonn

AUTHOR

Amiram Eldar, Sep 30 2019

STATUS

approved

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Last modified September 29 07:08 EDT 2020. Contains 337425 sequences. (Running on oeis4.)