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 A317534 #18 Jul 17 2021 06:43:02 %S A317534 24,32,40,48,54,56,60,64,72,80,84,88,90,96,104,108,112,120,126,128, %T A317534 132,135,136,140,144,150,152,156,160,162,168,176,180,184,189,192,198, %U A317534 200,204,208,216,220,224,228,232,234,240,243,248,250,252,256,260,264,270 %N A317534 Numbers k such that the poset of factorizations of k, ordered by refinement, is not a lattice. %C A317534 Includes 2^k for all k > 4. %C A317534 Conjecture: Let S be the set of all numbers whose prime signature is either {1,3}, {5}, or {1,1,2}. Then the sequence consists of all multiples of elements of S. - _David A. Corneth_, Jul 31 2018. %D A317534 R. P Stanley, Enumerative Combinatorics Vol. 1, Sec. 3.3. %H A317534 Wikipedia, <a href="https://en.wikipedia.org/wiki/Lattice_(order)">Lattice (order)</a> %e A317534 In the poset of factorizations of 24, the factorizations (2*2*6) and (2*3*4) have two least-upper bounds, namely (2*12) and (4*6), so this poset is not a lattice. %Y A317534 Cf. A001055, A007716, A025487, A045778, A065036, A162247, A265947, A281113, A317142, A317144, A317145, A317146. %K A317534 nonn %O A317534 1,1 %A A317534 _Gus Wiseman_, Jul 30 2018