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 A065149 #16 Jun 19 2018 05:22:41
%S A065149 10,33,65,136,145,261,385,451,897,946,1281,1441,1665,1729,2241,2353,
%T A065149 3585,5185,6721,7201,8380,8911,8961,11521,11782,12673,12801,17101,
%U A065149 18241,20737,25201,26625,26677,26937,29697,29953,30721,30889,32896
%N A065149 Composite numbers m such that phi(m)*sigma(m) is divisible by m-1.
%H A065149 Harry J. Smith, <a href="/A065149/b065149.txt">Table of n, a(n) for n = 1..500</a>
%F A065149 (A000010(m)*A000203(m)) mod (m-1) = 0, m is composite.
%e A065149 m=136, phi(136)=64, sigma(136)=270, product=17280, quotient=128; for primes the formula holds.
%p A065149 with(numtheory): select(m->modp(phi(m)*sigma(m),m-1)=0 and not isprime(m),[$2..40000]); # _Muniru A Asiru_, Jun 18 2018
%t A065149 Do[s=EulerPhi[n]*DivisorSigma[1, n]; If[IntegerQ[s/(n-1)]&&!PrimeQ[n], Print[n]], {n, 1, 100000}]
%o A065149 (PARI) { n=0; for (m=2, 10^9, s=eulerphi(m)*sigma(m); if (s%(m-1) == 0 && !isprime(m), write("b065149.txt", n++, " ", m); if (n==500, return)) ) } \\ _Harry J. Smith_, Oct 12 2009
%o A065149 (GAP) Filtered([2..40000],m->Phi(m)*Sigma(m) mod (m-1)=0 and not IsPrime(m)); # _Muniru A Asiru_, Jun 18 2018
%Y A065149 Cf. A000010, A000203, A062354, A011257.
%K A065149 nonn
%O A065149 1,1
%A A065149 _Labos Elemer_, Oct 18 2001
%E A065149 Offset changed from 0 to 1 by _Harry J. Smith_, Oct 12 2009