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 A306303 #13 Nov 20 2023 16:32:25
%S A306303 95,110,220,312,330,371,432,440,510,525,550,624,660,714,770,864,880,
%T A306303 936,990,995,1111,2480,4100,5115,5125,5134,5135,5625,6120,6432,6794,
%U A306303 8100,8145,9225,9864,9950,9995,10250,11100,11110,12864,15375,16200,20500,22200,22220
%N A306303 Numbers that appear in the concatenation in decreasing order of their aliquot parts.
%C A306303 The first terms that appear in both the concatenations in increasing and decreasing order are 510, 550, 624, 714, 1111, 5625, 50100, 51020, 53125, 56250, 67134, ...
%H A306303 Paolo P. Lava, <a href="/A306303/b306303.txt">Table of n, a(n) for n = 1..250</a>
%e A306303 Aliquot parts of 95 are 1, 5, 19 and their concatenation in decreasing order is 1951 where 95 appears.
%p A306303 with(numtheory): P:=proc(n) local a,b,k;
%p A306303 a:=sort([op(divisors(n) minus {n})]); b:=a[nops(a)];
%p A306303 for k from nops(a) by -1 to 2 do b:=b*10^(ilog10(a[k-1])+1)+a[k-1]; od;
%p A306303 if searchtext(convert(n,string),convert(b,string))>0
%p A306303 then n; fi; end: seq(P(i),i=2..22220);
%t A306303 Select[Range[23000],SequenceCount[Flatten[IntegerDigits/@Reverse[Most[Divisors[ #]]]],IntegerDigits[ #]]>0&] (* _Harvey P. Dale_, Nov 20 2023 *)
%Y A306303 Cf. A056538, A248323.
%K A306303 nonn,base,easy
%O A306303 1,1
%A A306303 _Paolo P. Lava_, Feb 05 2019