%I
%S 1,4,4,90,176,289,1170,6640,21569,21569,54421
%N a(n) is the number of digits in the decimal representation of the smallest power of 6 that contains n consecutive identical digits.
%C Number of digits in 6^k is equal to floor(1 + k*log_10(6)).
%t k = 0; Join[{1}, Table[While[d = IntegerDigits[6^k]; prt = Partition[Differences[d], n  1, 1]; ! MemberQ[prt, Table[0, {n  1}]], k++]; Length[d], {n, 2, 8}]] (* _T. D. Noe_, Oct 03 2012 *)
%Y Cf. A215729, A215735.
%K nonn,base
%O 1,2
%A _V. Raman_, Sep 27 2012
%E a(11) added by _V. Raman_, Nov 23 2013
