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 A349688 #11 Nov 28 2021 02:56:17
%S A349688 1,6,24,28,30,42,54,66,70,78,84,90,96,102,114,120,138,140,174,186,220,
%T A349688 222,246,258,264,270,282,308,318,330,342,348,354,364,366,402,426,438,
%U A349688 474,476,496,498,532,534,582,606,618,642,644,654,660,672,678,744,760,762
%N A349688 Numbers k such that the sequence of elements of the continued fraction of the abundancy index of k is palindromic.
%C A349688 All the multiply-perfect numbers (A007691) are terms of this sequence, since the continued fraction of their abundancy index contains a single element.
%H A349688 Amiram Eldar, <a href="/A349688/b349688.txt">Table of n, a(n) for n = 1..10000</a>
%e A349688 24 is a term since the sequence of elements of the abundancy index of 24, sigma(24)/24 = 5/2 = 2 + 1/2, is {2, 2}, which is palindromic.
%e A349688 42 is a term since the sequence of elements of the abundancy index of 42, sigma(42)/42 = 16/7 = 2 + 1/(3 + 1/2), is {2, 3, 2}, which is palindromic.
%t A349688 q[n_] := PalindromeQ[ContinuedFraction[DivisorSigma[1, n]/n]]; Select[Range[1000], q]
%o A349688 (PARI) isok(k) = my(v=contfrac(sigma(k)/k)); v == Vecrev(v); \\ _Michel Marcus_, Nov 25 2021
%Y A349688 Cf. A349685.
%Y A349688 A007691 and A349686 are subsequences.
%Y A349688 Similar sequence: A349477.
%K A349688 nonn
%O A349688 1,2
%A A349688 _Amiram Eldar_, Nov 25 2021