A217183 - OEIS

A217183

a(n) is the number of digits in the decimal representation of the smallest power of n that contains eight consecutive identical digits.

%I #9 Oct 03 2012 14:31:42

%S 2576,3684,2576,1951,6640,5220,4012,3684,9,3107,2623,6107,1207,5916,

%T 4217,7114,4999,6018,11,3396,6511,3732,6279,1951,990,4237,3877,4676,

%U 12,6051,4078,4731,5263,1838,10317,1086,5173,9186,13,11285,5740,9697,1064,5297

%N a(n) is the number of digits in the decimal representation of the smallest power of n that contains eight consecutive identical digits.

%C Number of digits in n^k is equal to floor(1 + k*log_10(n)).

%H V. Raman, <a href="/A217183/b217183.txt">Table of n, a(n) for n = 2..100</a>

%t Table[k = 1; While[d = IntegerDigits[n^k]; ! MemberQ[Partition[Differences[d], 7, 1], {0, 0, 0, 0, 0, 0, 0}], k++]; Length[d], {n, 2, 10}] (* _T. D. Noe_, Oct 03 2012 *)

%Y Cf. A217163, A217173.

%K nonn,base

%O 2,1

%A _V. Raman_, Sep 27 2012