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A217188
a(n) is the number of digits in the decimal representation of the smallest power of 6 that contains n consecutive identical digits.
0
1, 4, 4, 90, 176, 289, 1170, 6640, 21569, 21569, 54421
OFFSET
1,2
COMMENTS
Number of digits in 6^k is equal to floor(1 + k*log_10(6)).
MATHEMATICA
k = 0; Join[{1}, Table[While[d = IntegerDigits[6^k]; prt = Partition[Differences[d], n - 1, 1]; ! MemberQ[prt, Table[0, {n - 1}]], k++]; Length[d], {n, 2, 8}]] (* T. D. Noe, Oct 03 2012 *)
CROSSREFS
Sequence in context: A131592 A317868 A224092 * A092209 A068337 A009534
KEYWORD
nonn,base
AUTHOR
V. Raman, Sep 27 2012
EXTENSIONS
a(11) added by V. Raman, Nov 23 2013
STATUS
approved