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%I #17 Feb 19 2024 01:54:41
%S 8,64,640,6400,64000,640000,6400000,64000000,640000000,6400000000,
%T 64000000000,640000000000,6400000000000,64000000000000,
%U 640000000000000,6400000000000000,64000000000000000,640000000000000000
%N a(1) = 8; for n > 0, a(n+1) = a(n) * sum of digits of a(n).
%C After the 2nd element, every element has the same beginning.
%C a(3+k) = 10 * a(2+k).
%H Reinhard Zumkeller, <a href="/A047900/b047900.txt">Table of n, a(n) for n = 1..250</a>
%F a(n+1) = A057147(a(n)). - _Reinhard Zumkeller_, Mar 19 2014
%t NestList[# Total[IntegerDigits[#]]&,8,20] (* or *) Join[{8},NestList[ 10#&,64,20]] (* _Harvey P. Dale_, Jul 03 2020 *)
%o (Haskell)
%o a047900 n = a047900_list !! (n-1)
%o a047900_list = iterate a057147 8 -- _Reinhard Zumkeller_, Mar 19 2014
%Y Cf. A047892 (start=2), A047912 (start=3), A047897 (start=5), A047898 (start=6), A047899 (start=7), A047901 (start=9), A047902 (start=11).
%K easy,nonn,base
%O 1,1
%A Miklos SZABO (mike(AT)ludens.elte.hu)
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