A217181 a(n) is the number of digits in the decimal representation of the smallest power of n that contains six consecutive identical digits.

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

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