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A131548 Least power of 3 having exactly n consecutive 5's in its decimal representation. 1
8, 27, 39, 33, 274, 2076, 5173, 8880, 67390, 206131 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

a(3)=39 because 3^39(i.e. 4052555153018976267) is the smallest power of 3 to contain a run of 3 consecutive fives in its decimal form.

MATHEMATICA

a = ""; Do[ a = StringJoin[a, "5"]; b = StringJoin[a, "5"]; k = 1; While[ StringPosition[ ToString[3^k], a] == {} || StringPosition[ ToString[3^k], b] != {}, k++ ]; Print[k], {n, 1, 10} ]

CROSSREFS

Sequence in context: A066215 A086213 A175050 * A063142 A144619 A032553

Adjacent sequences:  A131545 A131546 A131547 * A131549 A131550 A131551

KEYWORD

more,nonn,base

AUTHOR

Shyam Sunder Gupta (guptass(AT)rediffmail.com), Aug 26 2007

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Last modified February 15 14:57 EST 2012. Contains 205823 sequences.