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 A074986 #8 Feb 04 2025 23:37:37
%S A074986 1,3,5,9,11,18,20,28,32,39,41,62,64,71,78,94,96,117,119,140,147,154,
%T A074986 156,214,218,225,233,254,256,301,303,335,342,349,356,440,442,449,456,
%U A074986 514,516,561,563,584,605,612,614,766,770,791,798,819,821,879,886,944,951
%N A074986 Number of nonempty subsets of {1,2,3,...,n} that are closed under both GCD and LCM.
%C A074986 I.e. number of division lattices with values from 1 to n. - _Franklin T. Adams-Watters_, Sep 21 2006
%H A074986 Sean A. Irvine, <a href="/A074986/b074986.txt">Table of n, a(n) for n = 1..200</a>
%Y A074986 Cf. A051839, A122977, A122978.
%K A074986 nonn
%O A074986 1,2
%A A074986 _John W. Layman_, Oct 02 2002
%E A074986 More terms from _Franklin T. Adams-Watters_, Sep 21 2006