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a(1) = 1, a(n)= number obtained by replacing each digit of a(n-1) with eight times its value.
6

%I #12 Oct 27 2023 22:05:37

%S 1,8,64,4832,32642416,241648321632848,1632848326424168482416643264,

%T 84824166432642416483216328486432641632848483224164832,

%U 64326416328484832241648321632848326424168482416643264483224164832848241664326432642416163284832642416

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

%H John Cerkan, <a href="/A061586/b061586.txt">Table of n, a(n) for n = 1..12</a>

%t NestList[FromDigits[Flatten[IntegerDigits/@(8*IntegerDigits[#])]]&,1,10] (* _Harvey P. Dale_, Sep 22 2012 *)

%o (Python)

%o def A061586_first(n):

%o an = "1"

%o cnt = 1

%o a061586 = []

%o while cnt < n:

%o a061586.append(int(an))

%o newan = ""

%o for i in an:

%o newan += str(8*int(i))

%o an = newan

%o cnt += 1

%o a061586.append(int(an))

%o return a061586 # _John Cerkan_, May 25 2018

%Y Cf. A061581-A061587.

%K nonn,base,easy

%O 1,2

%A _Amarnath Murthy_, May 13 2001

%E More terms from Larry Reeves (larryr(AT)acm.org) and _Asher Auel_, May 15 2001