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a(1) = 10, a(n) = a(n-1) times the number of digits in a(n-1).
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%I #12 Feb 09 2014 22:45:34

%S 10,20,40,80,160,480,1440,5760,23040,115200,691200,4147200,29030400,

%T 232243200,2090188800,20901888000,229920768000,2759049216000,

%U 35867639808000,502146957312000,7532204359680000

%N a(1) = 10, a(n) = a(n-1) times the number of digits in a(n-1).

%C For every n there is a least number k such that n! divides a(m) for all m > k. Subsidiary sequence: least k such that n! divides a(k).

%e Next term after 160 is 160*3 = 480.

%t NestList[# IntegerLength[#] &, 10, 20] (* _Harvey P. Dale_, Feb 04 2011 *)

%K base,easy,nonn

%O 1,1

%A _Amarnath Murthy_, Aug 14 2005

%E More terms from _Harvey P. Dale_, Feb 04 2011