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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.

A348121 Numbers having more nonunitary than unitary prime divisors.

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%I A348121 #11 Oct 02 2021 03:47:24
%S A348121 4,8,9,16,25,27,32,36,49,64,72,81,100,108,121,125,128,144,169,180,196,
%T A348121 200,216,225,243,252,256,288,289,300,324,343,360,361,392,396,400,432,
%U A348121 441,450,468,484,500,504,512,529,540,576,588,600,612,625,648,675,676,684
%N A348121 Numbers having more nonunitary than unitary prime divisors.
%C A348121 First differs from A080366 at n = 20.
%C A348121 The first 19 terms are also the first 19 powerful numbers (A001694) above 1. a(20) = 180 is the least nonpowerful term.
%C A348121 Numbers k such that A056169(k) < A056170(k).
%H A348121 Amiram Eldar, <a href="/A348121/b348121.txt">Table of n, a(n) for n = 1..10000</a>
%e A348121 4 = 2^2 is a term since it has 1 nonunitary prime divisor, 2, and no unitary prime divisors.
%e A348121 180 = 2^2 * 3^2 * 5 is a term since it has 2 nonunitary prime divisors, 2 and 3, and one unitary prime divisor, 5.
%t A348121 q[n_] := 2*Count[(e = FactorInteger[n][[;; , 2]]), 1] < Length[e]; Select[Range[700], q]
%Y A348121 Cf. A056169, A056170, A348097.
%Y A348121 Subsequence of A013929.
%Y A348121 A001694 is a subsequence.
%K A348121 nonn
%O A348121 1,1
%A A348121 _Amiram Eldar_, Oct 01 2021