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A131547
Least power of 3 having exactly n consecutive 6's in its decimal representation.
9
8, 33, 34, 275, 1385, 539, 8881, 22792, 90785, 107188, 704996, 1847533, 5756980, 9995031, 68353788
OFFSET
1,1
EXAMPLE
a(3)=34 because 3^34(i.e. 16677181699666569) is the smallest power of 3 to contain a run of 3 consecutive sixes in its decimal form.
MATHEMATICA
a = ""; Do[ a = StringJoin[a, "6"]; b = StringJoin[a, "6"]; k = 1; While[ StringPosition[ ToString[3^k], a] == {} || StringPosition[ ToString[3^k], b] != {}, k++ ]; Print[k], {n, 1, 10} ]
KEYWORD
more,nonn,base
AUTHOR
Shyam Sunder Gupta, Aug 26 2007
EXTENSIONS
a(11)-a(14) from Lars Blomberg, Feb 02 2013
a(15) from Bert Dobbelaere, Mar 04 2019
STATUS
approved