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 A063970 #16 Feb 02 2023 03:08:07
%S A063970 2,12,1234612,1247915831639077814156283086536173061234612
%N A063970 a(1) = 2; for n>1, write down all divisors of the previous term in order of magnitude.
%C A063970 The next term has 3104 digits. - _Harvey P. Dale_, May 28 2017
%e A063970 Divisors of a(3)={1, 2, 4, 79, 158, 316, 3907, 7814, 15628, 308653, 617306, 1234612}
%t A063970 NestList[FromDigits[Flatten[IntegerDigits/@Divisors[#]]]&,2,4] (* _Harvey P. Dale_, May 28 2017 *)
%o A063970 (Python)
%o A063970 from sympy import divisors
%o A063970 def aupton(terms):
%o A063970 alst = [2]
%o A063970 for n in range(2, terms+1):
%o A063970 alst.append(int("".join(str(d) for d in divisors(alst[-1]))))
%o A063970 return alst
%o A063970 print(aupton(4)) # _Michael S. Branicky_, Feb 12 2021
%Y A063970 Cf. A006919, A056938.
%K A063970 nonn,base
%O A063970 1,1
%A A063970 _Labos Elemer_, Sep 05 2001
%E A063970 Next term has more than 3000 decimal digits.