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%I #4 Dec 05 2013 19:55:32
%S 1,0,2,4,5,6,9,12,15,10,11,24,25,8,30,40,41,18,28,20,27,46,31,52,50,
%T 32,38,60,61,80,55,36,44,120,45,48,78,26,64,160,93,14,23,140,95,98,21,
%U 76,51,100,56,92,84,34,85,68,3,62,115,180,81,74,88,128,75,58,72,124,134
%N a(0)=1; a(n) for n > 0 is the smallest number not used earlier such that the concatenation of a(0),...,a(n) is a multiple of n+1.
%C Does every nonnegative integer eventually appear?
%e Concatenation of a(0),...,a(6) is 1024569, not used so far are 3, 7, 8, 10, 11, 12, ..., the smallest of these that appended to 1024569 gives a multiple of 8 is 12: 102456912 = 8*12807114, hence a(7) = 12.
%Y Cf. A100769, A099552, A051883, A073893.
%K base,nonn
%O 0,3
%A _Amarnath Murthy_, Aug 17 2002
%E Edited and extended by _Klaus Brockhaus_, Mar 28 2006