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A195908
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Powers of 7 which have no zero in their decimal expansion.
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25
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OFFSET
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1,2
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COMMENTS
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Probably finite. Is 378818692265664781682717625943 the largest term?
No further terms up to 7^50,000, a number with 42,255 digits. - Harvey P. Dale, Jul 14 2022
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LINKS
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FORMULA
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MATHEMATICA
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Select[7^Range[0, 50], DigitCount[#, 10, 0]==0&] (* Harvey P. Dale, Jul 14 2022 *)
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PROG
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(PARI) for( n=1, 9999, is_A052382(7^n) && print1(7^n, ", "))
(Magma) [7^n: n in [0..3*10^4] | not 0 in Intseq(7^n)]; // Bruno Berselli, Sep 26 2011
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CROSSREFS
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Cf. A195942, A195943, A195944, A195945, A195946, A195948, A007377, A008839, A030700, A030701, A030702, A030703, A030704, A030705, A030706.
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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Keyword:fini removed by Jianing Song, Jan 28 2023 as finiteness is only conjectured.
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STATUS
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approved
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