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a(1) = 7, a(n) = smallest (nontrivial) multiple of a(n-1) containing n digits, a(n) not equal to 10*a(n-1).
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%I #6 Jan 20 2015 18:44:48

%S 7,14,112,1008,11088,121968,1097712,12074832,108673488,1195408368,

%T 10758675312,118345428432,1065108855888,11716197414768,

%U 105445776732912,1159903544062032,10439131896558288,114830450862141168

%N a(1) = 7, a(n) = smallest (nontrivial) multiple of a(n-1) containing n digits, a(n) not equal to 10*a(n-1).

%H Harvey P. Dale, <a href="/A080451/b080451.txt">Table of n, a(n) for n = 1..1000</a>

%t nxt[n_]:=Module[{k=2,len=IntegerLength[n]+1},While[IntegerLength[ k*n]<len || Divisible[k*n,10],k++];k*n] (* _Harvey P. Dale_, Jan 20 2015 *)

%Y Cf. A080445, A080446, A080447, A080448, A080449, A080450, A080452, A080453.

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Feb 23 2003

%E More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003