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%I #2 Mar 30 2012 17:40:41
%S 4,5,6,6,7,8,8,9,19,20,21,22,23,24,25,27,28,29,30,31,32,33,34,35,36,
%T 37,38,39,40,41,42,43,44,45,45,46,47,48,49,50,51,52,53,54,55,56,56,57,
%U 58,59,60,61,62,63,63,64,65,66,67,68,69,69,70,71,72,73,74,74,75,76,77,78
%N Floor of the base n Log of the number obtained concatenating n with itself n times.
%C a(100)=149, a(1000)=1333, a(10000)=12499.
%e a(8)=8 since 88888888=8^8.802.
%t Table[Floor@Log[n,FromDigits@Flatten@IntegerDigits@Array[n &, n]], {n,2,60}]
%K base,nonn
%O 2,1
%A _Giovanni Resta_, Apr 04 2006