

A348032


Multiplyperfect numbers k that do not have a divisor d such that sigma(d)*d = k.


1



2178540, 45532800, 459818240, 1476304896, 14182439040, 31998395520, 43861478400, 51001180160, 518666803200, 704575228896, 13661860101120, 30823866178560, 181742883469056, 740344994887680, 796928461056000, 6088728021160320, 20158185857531904, 212517062615531520, 622286506811515392, 69357059049509038080, 87934476737668055040
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OFFSET

1,1


COMMENTS

Question: Is A323653 a subsequence of this sequence? See also conjecture in A348033.


LINKS



MATHEMATICA

With[{s = DeleteCases[Map[ToExpression[#] &, Import["https://oeis.org/A007691/b007691.txt", "Data"]], _?(Length[#] == 0 &)][[All, 1]]}, Select[s[[1 ;; 45]], Function[k, NoneTrue[Divisors[k], # DivisorSigma[1, #] == k &]]]] (* Michael De Vlieger, Sep 28 2021, using bfile at A007691 *)


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



