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 A368714 #12 Sep 08 2024 17:11:17 %S A368714 1,4,9,12,16,18,20,25,28,36,44,45,48,49,50,52,60,63,64,68,75,76,80,81, %T A368714 84,90,92,98,99,100,112,116,117,121,124,126,132,140,144,147,148,150, %U A368714 153,156,162,164,169,171,172,175,176,180,188,192,196,198,204,207,208 %N A368714 Numbers whose maximal exponent in their prime factorization is even. %C A368714 First differs from A240112 at n = 30. %C A368714 Numbers k such that A051903(k) is even. %C A368714 The asymptotic density of this sequence is Sum_{k>=2} (-1)^k * (1 - 1/zeta(k)) = 0.27591672059822700769... . %H A368714 Amiram Eldar, <a href="/A368714/b368714.txt">Table of n, a(n) for n = 1..10000</a> %t A368714 Select[Range[210], # == 1 || EvenQ[Max[FactorInteger[#][[;;, 2]]]] &] %o A368714 (PARI) lista(kmax) = for(k = 1, kmax, if(k == 1 || !(vecmax(factor(k)[,2])%2), print1(k, ", "))); %Y A368714 Cf. A051903, A240112. %Y A368714 Subsequences: A000290, A000302, A000583, A001014, A001016, A001025, A008454, A062503, A067259. %Y A368714 Similar sequences: A060476, A074661, A096432, A336064, A368715. %K A368714 nonn,easy %O A368714 1,2 %A A368714 _Amiram Eldar_, Jan 04 2024