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 A048747 #21 Jul 04 2021 16:04:53
%S A048747 6,14,20,21,22,27,33,38,39,45,46,49,57,62,65,85,86,87,91,93,94,99,111,
%T A048747 116,118,123,125,129,133,134,141,142,150,158,164,166,169,183,185,188,
%U A048747 201,206,207,213,214,215,217,219,236,237,249,254,259,261,262,267,278
%N A048747 Factor composite n, divide sum of divisors by number of divisors; append n to sequence if quotient is integral and not previously seen.
%H A048747 Amiram Eldar, <a href="/A048747/b048747.txt">Table of n, a(n) for n = 1..10000</a>
%e A048747 a(3)=20; for n=20 the sum of divisors is 42; number of divisors is 6; 42/6=7. The quotient 7 is the mean divisor and this is the first time that 7 has occurred.
%t A048747 (Select[{Mean[Divisors[#]], #}& /@ Select[Range[300], CompositeQ], IntegerQ[#[[1]]]&] // Sort // Split[#, #1[[1]] == #2[[1]]&]&)[[All, 1]][[All, 2]] // Sort (* _Jean-François Alcover_, Oct 31 2017 *)
%Y A048747 Gives first occurrence of terms in A023883.
%Y A048747 Cf. A000005, A000203, A048748.
%K A048747 nonn
%O A048747 1,1
%A A048747 _Enoch Haga_
%E A048747 Title clarified by _Sean A. Irvine_, Jul 03 2021