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A061586 a(1) = 1, a(n)= number obtained by replacing each digit of a(n-1) with eight times its value.

%I A061586 #12 Oct 27 2023 22:05:37
%S A061586 1,8,64,4832,32642416,241648321632848,1632848326424168482416643264,
%T A061586 84824166432642416483216328486432641632848483224164832,
%U A061586 64326416328484832241648321632848326424168482416643264483224164832848241664326432642416163284832642416
%N A061586 a(1) = 1, a(n)= number obtained by replacing each digit of a(n-1) with eight times its value.
%H A061586 John Cerkan, <a href="/A061586/b061586.txt">Table of n, a(n) for n = 1..12</a>
%t A061586 NestList[FromDigits[Flatten[IntegerDigits/@(8*IntegerDigits[#])]]&,1,10] (* _Harvey P. Dale_, Sep 22 2012 *)
%o A061586 (Python)
%o A061586 def A061586_first(n):
%o A061586     an = "1"
%o A061586     cnt = 1
%o A061586     a061586 = []
%o A061586     while cnt < n:
%o A061586         a061586.append(int(an))
%o A061586         newan = ""
%o A061586         for i in an:
%o A061586             newan += str(8*int(i))
%o A061586         an = newan
%o A061586         cnt += 1
%o A061586     a061586.append(int(an))
%o A061586     return a061586 # _John Cerkan_, May 25 2018
%Y A061586 Cf. A061581-A061587.
%K A061586 nonn,base,easy
%O A061586 1,2
%A A061586 _Amarnath Murthy_, May 13 2001
%E A061586 More terms from Larry Reeves (larryr(AT)acm.org) and _Asher Auel_, May 15 2001