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 A139554 #7 Mar 04 2018 17:45:33
%S A139554 1,1,1,1,1,1,1,1,2,2,2,2,6,6,6,6,12,12,12,12,60,60,60,60,60,60,60,60,
%T A139554 420,420,420,420,840,840,840,840,2520,2520,2520,2520,2520,2520,2520,
%U A139554 2520,27720,27720,27720,27720,27720,27720,27720,27720,360360,360360
%N A139554 a(n) = lcm(1..floor(n/4)).
%C A139554 Row products of A139553.
%t A139554 Join[{1,1,1,1},Table[LCM@@Range[Floor[n/4]],{n,4,60}]] (* _Harvey P. Dale_, May 24 2012 *)
%Y A139554 Cf. A139553, A003418.
%K A139554 nonn
%O A139554 0,9
%A A139554 _Mats Granvik_, Apr 27 2008