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%I #18 Oct 27 2023 22:05:37
%S 1,5,25,1025,501025,250501025,10250250501025,501025010250250501025,
%T 2505010250501025010250250501025,
%U 1025025050102502505010250501025010250250501025
%N a(1) = 1, a(n) is the number obtained by replacing each digit of a(n-1) with five times its value.
%C Number of digits of each term is the sequence A038718. - _Dmitry Kamenetsky_, Jan 17 2009
%H John Cerkan, <a href="/A061583/b061583.txt">Table of n, a(n) for n = 1..17</a>
%p a:= proc(n) option remember; `if`(n=1, 1, (s-> parse(cat(
%p seq(parse(s[i])*5, i=1..length(s)))))(""||(a(n-1))))
%p end:
%p seq(a(n), n=1..10); # _Alois P. Heinz_, May 25 2018
%t NestList[FromDigits[Flatten[IntegerDigits/@(5*IntegerDigits[#])]]&,1,10] (* _Harvey P. Dale_, Dec 31 2013 *)
%o (Python)
%o def A061583_first(n):
%o an = "1"
%o a061583 = []
%o while n > 1:
%o a061583.append(int(an))
%o newan = ""
%o for i in an:
%o newan += str(5*int(i))
%o an = newan
%o n -= 1
%o a061583.append(int(an))
%o return a061583 # _John Cerkan_, May 25 2018
%Y Cf. A061581, A061582, A061584, A061585, A061586, 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
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