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 A349685 #14 Nov 28 2021 06:42:29
%S A349685 1,1,2,1,3,1,1,3,1,5,2,1,7,1,1,7,1,2,4,1,1,4,1,11,2,3,1,13,1,1,2,2,1,
%T A349685 1,1,2,1,1,15,1,17,2,6,1,19,2,10,1,1,1,10,1,1,1,1,3,1,23,2,2,1,4,6,1,
%U A349685 1,1,1,1,2,1,2,13,2,1,29,2,2,2,1,31,1,1,31
%N A349685 Irregular triangle read by rows: the n-th row contains the elements in the continued fraction of the abundancy index of n.
%C A349685 The abundancy index of n is sigma(n)/n = A000203(n)/n = A017665(n)/A017666(n).
%C A349685 For a prime p, the p-th row has a length 2 with a(p, 1) = 1 and a(p, 2) = p.
%C A349685 For multiply-perfect numbers m (A007691), the m-th row has a length 1, since their abundancy index is an integer. In particular, for a perfect number m (A000396), the m-th row has a length 1 with a(m, 1) = 2.
%H A349685 Amiram Eldar, <a href="/A349685/b349685.txt">Table of n, a(n) for n = 1..10489</a> (rows 1..2000)
%e A349685 The first ten rows of the triangle are:
%e A349685 1,
%e A349685 1, 2,
%e A349685 1, 3,
%e A349685 1, 1, 3,
%e A349685 1, 5,
%e A349685 2,
%e A349685 1, 7,
%e A349685 1, 1, 7,
%e A349685 1, 2, 4,
%e A349685 1, 1, 4,
%e A349685 ...
%t A349685 row[n_] := ContinuedFraction[DivisorSigma[1, n]/n]; Table[row[k], {k, 1, 32}] // Flatten
%o A349685 (PARI) row(n) = contfrac(sigma(n)/n); \\ _Michel Marcus_, Nov 25 2021
%Y A349685 Cf. A000203, A000396, A007691, A017665, A017666, A071862 (row lengths), A071865, A349473.
%K A349685 nonn,tabf
%O A349685 1,3
%A A349685 _Amiram Eldar_, Nov 25 2021