A217182 - OEIS

A217182

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

%I #11 Oct 03 2012 14:28:54

%S 293,1014,293,1948,1170,1658,293,1014,8,1378,2092,571,1207,3058,293,

%T 3045,1866,1203,10,1435,1434,325,4014,1948,990,1014,1019,2291,11,427,

%U 2576,1420,3408,1838,2112,1086,1868,713,12,1428,2190,1332,1064,2770,1881,917,560

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

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

%H V. Raman, <a href="/A217182/b217182.txt">Table of n, a(n) for n = 2..1000</a>

%t Table[k = 1; While[d = IntegerDigits[n^k]; ! MemberQ[Partition[Differences[d], 6, 1], {0, 0, 0, 0, 0, 0}], k++]; Length[d], {n, 2, 100}] (* _T. D. Noe_, Oct 03 2012 *)

%Y Cf. A217162, A217172.

%K nonn,base

%O 2,1

%A _V. Raman_, Sep 27 2012