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 A084191 #12 Dec 16 2021 07:37:53
%S A084191 1,1,1,2,3,36,10,60,21,157080,36,2394591020640,330,438900,702,185640,
%T A084191 105,392201962392240,680,47347883887966200,450574740,3183089069160,210
%N A084191 a(n) = A084190(A084190(n)).
%C A084191 Next term: a(24) = A084190(53130) > 10^91.
%C A084191 B-file goes up to n=59 because a(60) has 1503 digits. - _Robert Israel_, Sep 04 2019
%H A084191 Robert Israel, <a href="/A084191/b084191.txt">Table of n, a(n) for n = 1..59</a>
%p A084191 A084190:= n -> ilcm(op(map(`-`,numtheory:-divisors(n) minus {1},1))):
%p A084191 map(A084190@A084190,[$1..30]); # _Robert Israel_, Sep 04 2019
%t A084191 b[n_] := LCM @@ (Rest[Divisors[n]] - 1);
%t A084191 a[n_] := If[n <= 2, 1, b@b@n];
%t A084191 Array[a, 59] (* _Jean-François Alcover_, Dec 16 2021 *)
%Y A084191 Cf. A084190.
%K A084191 nonn
%O A084191 1,4
%A A084191 _Reinhard Zumkeller_, May 18 2003