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A131550
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a(n) is the least exponent e such that 3^e has exactly n consecutive 3's in its decimal representation.
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9
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1, 31, 119, 185, 511, 2341, 9671, 7721, 67449, 364579, 513334, 639227, 6250772, 30377688, 82011443, 78927181
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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a(3)=119 because 3^119 (i.e., 599003433304810403471059943169868346577158542512617035467) is the smallest power of 3 to contain a run of 3 consecutive threes in its decimal form.
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MATHEMATICA
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a = ""; Do[ a = StringJoin[a, "3"]; b = StringJoin[a, "3"]; k = 1; While[ StringPosition[ ToString[3^k], a] == {} || StringPosition[ ToString[3^k], b] != {}, k++ ]; Print[k], {n, 1, 10} ]
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CROSSREFS
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KEYWORD
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more,nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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