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 A133454 #13 Jun 20 2021 08:30:41 %S A133454 4,6,12,60,5040,293318625600 %N A133454 Chain of 6 highly composite numbers generated when subject to the recurrence relation tau(a(n+1)) = a(n), with a(0)=3, where tau(n) is the number-of-divisors function A000005(n). %C A133454 We omit the seed a(0) from the sequence and keep the offset at 1, because 3 is not highly composite. - _R. J. Mathar_, Jun 20 2021 %e A133454 Since 4 is the HCN with 3 divisors, we have tau(4) = 3 and therefore a(1)=4; the HCN with 4 divisors is 6, so that tau(6) = 4 and hence a(2)=6; the HCN with 6 divisors is 12 so that tau(12) = 6, implying a(3)=12, ... %Y A133454 Cf. A002182. %Y A133454 A finite subsequence of A009287. %K A133454 fini,full,nonn %O A133454 1,1 %A A133454 _Lekraj Beedassy_, Dec 22 2007