

A327946


Nonunitary pseudoperfect numbers (A327945) that equal to the sum of a subset of their nonunitary divisors in a single way.


1



24, 36, 80, 112, 200, 312, 352, 392, 408, 416, 456, 552, 588, 684, 696, 744, 888, 984, 1032, 1088, 1116, 1128, 1216, 1272, 1332, 1416, 1464, 1472, 1548, 1608, 1692, 1704, 1752, 1856, 1896, 1908, 1936, 1984, 1992, 2124, 2136, 2196, 2288, 2328, 2412, 2424, 2472
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OFFSET

1,1


COMMENTS



LINKS



EXAMPLE

The nonunitary divisors of 36 are {2, 3, 6, 12, 18), and {6, 12, 18} is the only subset that sums to 36.


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 == 1, AppendTo[s, n]], {n, 1, 700}]; s


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



