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

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

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 A362582

Adjacent sequences: A217174 A217175 A217176 * A217178 A217179 A217180

Keyword

nonn,base

Author

V. Raman, Sep 27 2012

Status

approved