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 A009262 #29 Oct 12 2024 09:05:24
%S A009262 1,2,6,4,20,6,42,8,18,20,110,12,156,42,120,16,272,18,342,40,84,110,
%T A009262 506,24,100,156,54,84,812,120,930,32,660,272,840,36,1332,342,312,80,
%U A009262 1640,84,1806,220,360,506,2162,48,294,100,1632,312,2756,54,440,168,684,812,3422
%N A009262 a(n) = lcm(n, phi(n)).
%C A009262 This is a divisibility sequence: if n divides m, a(n) divides a(m). - _Franklin T. Adams-Watters_, Mar 30 2010
%C A009262 a(n) = n iff n is in A007694.
%C A009262 a(n) is a divisor of A299822(n). It is a proper divisor iff n is in A069209. - _Max Alekseyev_, Oct 11 2024
%H A009262 Enrique Pérez Herrero, <a href="/A009262/b009262.txt">Table of n, a(n) for n = 1..5000</a>
%H A009262 <a href="/index/Di#divseq">Index to divisibility sequences</a>
%F A009262 a(n) = A000010(n) * A109395(n) = n * A076512(n) = A299822(n) / gcd(A007947(n),phi(A007947(n))). - _Max Alekseyev_, Oct 11 2024
%p A009262 with(numtheory); A009262:=n->lcm(n, phi(n)); seq(A009262(n), n=1..100); # _Wesley Ivan Hurt_, Jan 29 2014
%t A009262 Table[LCM[n, EulerPhi[n]], {n, 100}] (* _Wesley Ivan Hurt_, Jan 29 2014 *)
%o A009262 (PARI) a(n)=lcm(eulerphi(n), n) \\ _Charles R Greathouse IV_, May 29 2016
%Y A009262 Cf. A000010, A007694, A007947, A052106, A069209, A076512, A109395, A174824.
%K A009262 nonn
%O A009262 1,2
%A A009262 _David W. Wilson_