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A323341 Numbers k whose unitary divisors have an even sum which is larger than 2k, but they cannot be partitioned into two disjoint parts whose sums are equal. 4
2394, 1452330, 5771934, 5786298, 5800662, 5834178, 5843754, 5858118, 5886846, 5905998, 5920362, 5929938, 5992182, 6035274, 6059214, 6078366, 6087942, 6102306, 6107094, 6121458, 6174126, 6202854, 6207642, 6245946, 6265098, 6274674, 6303402, 6336918, 6360858 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The unitary version of A171641.

LINKS

Table of n, a(n) for n=1..29.

MATHEMATICA

usigma[n_] := If[n == 1, 1, Times @@ (1 + Power @@@ FactorInteger[n])]; seq={}; Do[s=usigma[n]; If[OddQ[s] || s<=2n, Continue[]]; udiv = Select[Divisors[n], GCD[ #, n/# ] == 1 &]; If[Coefficient[Times @@ (1 + x^udiv) // Expand, x, s/2] == 0, AppendTo[seq, n]], {n, 1, 1500000}]; seq

CROSSREFS

Cf. A034448, A034683, A171641, A290466, A323342, A323343, A323344.

Sequence in context: A226149 A115931 A323344 * A108055 A286342 A204357

Adjacent sequences:  A323338 A323339 A323340 * A323342 A323343 A323344

KEYWORD

nonn

AUTHOR

Amiram Eldar, Jan 11 2019

STATUS

approved

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Last modified September 27 04:10 EDT 2021. Contains 347673 sequences. (Running on oeis4.)