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A248022 Achilles numbers which are coprime to the sum of their divisors. 1

%I

%S 392,800,968,1352,2312,2888,3087,3267,3872,4232,5408,6075,6125,6272,

%T 6728,7688,7803,9248,10952,11552,12800,13448,14283,14792,15125,15488,

%U 16928,17672,19208,20000,21632,22472,22707,25088,26912,27783,27848,29403,29768,30752,33275

%N Achilles numbers which are coprime to the sum of their divisors.

%H Amiram Eldar, <a href="/A248022/b248022.txt">Table of n, a(n) for n = 1..10000</a>

%t achillesQ[n_] := Block[{ls = Last /@ FactorInteger@ n}, Min@ ls > 1 == GCD @@ ls]; Select[ Range@ 35000, achillesQ[ #] && GCD[#, DivisorSigma[1, #]] == 1 &]

%Y Intersection of A052486 and A003624. - _Michel Marcus_, Sep 30 2014

%K nonn,easy

%O 1,1

%A _Robert G. Wilson v_, Sep 29 2014

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Last modified August 9 17:13 EDT 2022. Contains 356026 sequences. (Running on oeis4.)