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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
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, 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, 6, 8, 4, 6, 14, 12, 6, 12, 4, 2, 6, 8, 4, 6, 6, 4, 10, 4, 8, 12, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

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

LINKS

V. Raman, Table of n, a(n) for n = 2..10000

MATHEMATICA

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

CROSSREFS

Cf. A217157, A217167.

Sequence in context: A223171 A188942 A011258 * A157339 A029944 A197494

Adjacent sequences:  A217174 A217175 A217176 * A217178 A217179 A217180

KEYWORD

nonn,base

AUTHOR

V. Raman, Sep 27 2012

STATUS

approved

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Last modified December 14 01:33 EST 2019. Contains 329978 sequences. (Running on oeis4.)