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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A348962 Exponential harmonic numbers of type 1 (A348961) that are not squarefree.

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%I A348962 #14 Aug 06 2024 06:08:20
%S A348962 36,180,252,396,468,612,675,684,828,1044,1116,1260,1332,1350,1476,
%T A348962 1548,1692,1800,1908,1936,1980,2124,2196,2340,2412,2556,2628,2700,
%U A348962 2772,2844,2988,3060,3204,3276,3420,3492,3636,3708,3852,3924,4068,4140,4284,4572,4716
%N A348962 Exponential harmonic numbers of type 1 (A348961) that are not squarefree.
%C A348962 Sándor (2006) proved that all the squarefree numbers are exponential harmonic numbers of type 1.
%H A348962 Amiram Eldar, <a href="/A348962/b348962.txt">Table of n, a(n) for n = 1..10000</a>
%H A348962 József Sándor, <a href="https://citeseerx.ist.psu.edu/pdf/2936ca1cfcb9e3673ed4165dca32dbee1f4070f5">On exponentially harmonic numbers</a>, Scientia Magna, Vol. 2, No. 3 (2006), pp. 44-47.
%H A348962 József Sándor, <a href="https://blngcc.files.wordpress.com/2008/11/jozsel-sandor-selected-chaters-of-geometry-analysis-and-number-theory.pdf">Selected Chapters of Geomety, Analysis and Number Theory</a>, 2005, pp. 141-145.
%e A348962 36 = 2^2 * 3^2 is a term since it is not squarefree, A051377(36) = 72, 36 * A049419(36) = 36 * 4 = 144, so A051377(36) | 36 * A049419(36).
%t A348962 f[p_, e_] := p^e * DivisorSigma[0, e] / DivisorSum[e, p^# &]; ehQ[1] = True; ehQ[n_] := IntegerQ[Times @@ f @@@ FactorInteger[n]]; Select[Range[5000], ! SquareFreeQ[#] && ehQ[#] &]
%Y A348962 Intersection of A013929 and A348961.
%Y A348962 Cf. A049419, A005117, A051377, A054979, A054980, A348965.
%K A348962 nonn
%O A348962 1,1
%A A348962 _Amiram Eldar_, Nov 05 2021