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 A331442 #21 Jan 22 2020 17:49:21 %S A331442 5,8,10,9,11,11,11,11,8,11,11,11,11,11,11,11,11,11,11,11,11,11,20,16, %T A331442 41,31,28,28,31,54,21,9,36,11,24,23,32,10,37,42,12,27,46,16,40,27,6, %U A331442 19,45,13,42,42,37,61,37,98,93,18,44,33,19,59,35,54,166,131 %N A331442 Length of n-th chain in A331440. %H A331442 Lars Blomberg, <a href="/A331442/b331442.txt">Table of n, a(n) for n = 1..3000</a> %H A331442 Rémy Sigrist, <a href="/A331442/a331442.gp.txt">PARI program for A331442</a> %e A331442 When starting chain 9, A331440(77) is set to the first free number which is 17, and the chain becomes 17, 34, 68, 136, 272, 544, 1088, 2176 with length 8. %o A331442 (PARI) See Links section. %Y A331442 Cf. A331440, A331441. %K A331442 nonn,base %O A331442 1,1 %A A331442 _N. J. A. Sloane_, Jan 22 2020 %E A331442 Corrected a(9) and more terms from _Lars Blomberg_, Jan 22 2020