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A131613
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Numbers k such that the decimal expansion of 3^k contains no 9.
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8
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0, 1, 3, 4, 5, 7, 8, 11, 12, 16, 19, 20, 21, 29, 32, 56
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OFFSET
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1,3
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COMMENTS
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I conjecture that 56 is the last term.
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LINKS
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Table of n, a(n) for n=1..16.
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MATHEMATICA
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Join[{0}, Select[ Range@10000, FreeQ[ IntegerDigits[3^# ], 9] &]]
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PROG
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(Magma) [n: n in [0..1000] | not 9 in Intseq(3^n) ]; // Vincenzo Librandi, May 06 2015
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CROSSREFS
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Numbers k such that the decimal expansion of 3^k contains no m: A030700 (m=0), A131627 (m=1), A131625 (m=2), A131629 (m=3), A131618 (m=4), A131617 (m=5), A131616 (m=6), A131615 (m=7), A131614 (m=8), this sequence (m=9).
Cf. A007377.
Sequence in context: A047500 A359822 A257408 * A138494 A285531 A111801
Adjacent sequences: A131610 A131611 A131612 * A131614 A131615 A131616
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KEYWORD
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base,fini,nonn
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AUTHOR
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Shyam Sunder Gupta, Sep 01 2007
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EXTENSIONS
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Adapted Mma and initial 0 added by Vincenzo Librandi, May 06 2015
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STATUS
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approved
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