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 A371423 #11 Mar 23 2024 08:22:56
%S A371423 222,228,280,360,585,546,672,1008,1612,1568,1197,1040,1302,1536,2046,
%T A371423 2304,949,518,456,600,930,1152,1105,756,1120,1512,2400,3906,4992,7140,
%U A371423 12096,20320,24192,40800,70308,108416,135660,241920,490560,902208,1235456,1309440,2354688
%N A371423 Aliquot-like sequence based on the largest aliquot divisor of the sum of divisors of n (A371418) that starts with 222.
%C A371423 222 is the least number k for which the repeated iterations of the mapping k -> A371418(k) seem to generate an unbounded sequence.
%H A371423 Amiram Eldar, <a href="/A371423/b371423.txt">Table of n, a(n) for n = 1..1389</a>
%H A371423 Robert D. Carmichael, <a href="https://doi.org/10.5951/MT.14.6.0305">Empirical Results in the Theory of Numbers</a>, The Mathematics Teacher, Vol. 14, No. 6 (1921), pp. 305-310; <a href="https://www.jstor.org/stable/27950349">alternative link</a>. See p. 309.
%e A371423 a(1) = 222 by definition.
%e A371423 a(2) = A371418(a(1)) = A371418(222) = 228.
%e A371423 a(3) = A371418(a(2)) = A371418(228) = 280.
%t A371423 r[n_] := n/FactorInteger[n][[1, 1]]; f[n_] := r[DivisorSigma[1, n]]; NestList[f, 222, 60]
%o A371423 (PARI) f(n) = {my(s = sigma(n)); if(s == 1, 1, s/factor(s)[1, 1]);}
%o A371423 lista(nmax) = {my(m = 222); for(n = 1, nmax, print1(m, ", "); m = f(m));}
%Y A371423 Cf. A371418, A371421, A371422.
%Y A371423 Similar sequences: A008892, A323328, A361421.
%K A371423 nonn
%O A371423 1,1
%A A371423 _Amiram Eldar_, Mar 23 2024