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