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A131617
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Numbers k such that the decimal expansion of 3^k contains no 5.
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1
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0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 14, 15, 16, 17, 18, 19, 20, 23, 25, 29, 31, 41, 44, 52, 58, 81, 91
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OFFSET
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1,3
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COMMENTS
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I conjecture that 91 is the last term.
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LINKS
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MATHEMATICA
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Join[{0}, Select[ Range@10000, FreeQ[ IntegerDigits[3^# ], 5] &]
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PROG
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(Magma) [n: n in [0..1000] | not 5 in Intseq(3^n) ]; // Vincenzo Librandi, May 06 2015
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CROSSREFS
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Cf. similar sequences listed in A131613.
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KEYWORD
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base,fini,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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