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 A384185 #9 May 26 2025 23:51:35 %S A384185 1,2,4,6,12,5,8,24,3,7,18,16,30,36,48,10,32,14,72,9,60,96,120,19,64, %T A384185 13,40,144,21,35,56,38,28,90,26,240,15,192,384,44,76,360,88,80,180, %U A384185 168,114,54,288,112,264,25,41,33,256,98,20,55,312,128 %N A384185 Integers in A375491 in order of their first appearance. %C A384185 Does every positive integer appear in this sequence? %e A384185 a(1)=1 since the first squarefree integer (1) has 1 group of that order. %e A384185 a(2)=2 since the first squarefree integer not to have a(1)=1 group of its order (6) has 2 groups of its order. %e A384185 a(3)=4 since the first squarefree integer not to have a(1)=1 or a(2)=2 groups of its order (30) has 4 groups of its order. %Y A384185 Cf. A375491. %K A384185 nonn %O A384185 1,2 %A A384185 _Robin Jones_, May 21 2025