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A217177 a(n) is the number of digits in the decimal representation of the smallest power of n that contains two consecutive identical digits. 1

%I #8 Oct 03 2012 14:08:38

%S 5,6,5,8,4,6,6,6,3,2,3,11,4,3,5,9,7,7,3,3,2,9,6,9,8,6,12,8,3,9,8,2,4,

%T 4,5,11,4,7,4,9,5,7,2,5,4,4,6,6,4,12,7,6,11,2,7,8,4,8,4,6,4,6,6,4,2,4,

%U 6,8,4,6,14,12,6,12,4,2,6,8,4,6,6,4,10,4,8,12,2

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

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

%H V. Raman, <a href="/A217177/b217177.txt">Table of n, a(n) for n = 2..10000</a>

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

%Y Cf. A217157, A217167.

%K nonn,base

%O 2,1

%A _V. Raman_, Sep 27 2012

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Last modified April 18 20:21 EDT 2024. Contains 371781 sequences. (Running on oeis4.)