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.
%I A375145 #17 Feb 21 2025 08:10:08
%S A375145 8,16,24,27,32,40,48,54,56,64,72,80,81,88,96,104,108,112,120,125,128,
%T A375145 135,136,144,152,160,162,168,176,184,189,192,200,208,224,232,240,243,
%U A375145 248,250,256,264,270,272,280,288,296,297,304,312,320,324,328,336,343,344
%N A375145 Numbers whose prime factorization has exactly one exponent that is larger than 2.
%C A375145 Subsequence of A046099 and first differs from it at n = 35: A046099(35) = 216 = 2^3 * 3^3 is not a term of this sequence.
%C A375145 The asymptotic density of this sequence is (1/zeta(3)) * Sum_{p prime} 1/(p^3-1) = A286229 / A002117 = 0.16148833663564192901... .
%H A375145 Amiram Eldar, <a href="/A375145/b375145.txt">Table of n, a(n) for n = 1..10000</a>
%H A375145 <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>.
%e A375145 8 = 2^3 is a term since its prime factorization has exactly one exponent, 3, that is larger than 2.
%t A375145 q[n_] := Count[FactorInteger[n][[;; , 2]], _?(# > 2 &)] == 1; Select[Range[350], q]
%o A375145 (PARI) is(k) = #select(x -> x > 2, factor(k)[, 2]) == 1;
%Y A375145 Subsequence of A046099, A356862.
%Y A375145 Cf. A002117, A057521, A190641, A246549, A286229, A375146.
%K A375145 nonn,easy
%O A375145 1,1
%A A375145 _Amiram Eldar_, Aug 01 2024