

A217181


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


1



293, 257, 293, 760, 289, 148, 293, 257, 7, 502, 391, 365, 225, 607, 293, 431, 362, 185, 8, 1184, 1104, 325, 664, 1590, 398, 258, 184, 524, 9, 427, 684, 435, 532, 170, 749, 543, 497, 713, 10, 912, 630, 450, 148, 1029, 385, 755, 63, 432, 11, 822, 347, 330, 818, 537
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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[Partition[Differences[d], 5, 1], {0, 0, 0, 0, 0}], k++]; Length[d], {n, 2, 100}] (* T. D. Noe, Oct 03 2012 *)
spn6[n_]:=Module[{k=1}, While[SequenceCount[IntegerDigits[n^k], {x_, x_, x_, x_, x_, x_}]< 1, k++]; IntegerLength[n^k]]; Array[spn6, 55, 2] (* Harvey P. Dale, Jun 21 2022 *)


CROSSREFS

Cf. A217161, A217171.
Sequence in context: A190925 A232280 A202888 * A155140 A248210 A142284
Adjacent sequences: A217178 A217179 A217180 * A217182 A217183 A217184


KEYWORD

nonn,base


AUTHOR

V. Raman, Sep 27 2012


STATUS

approved



