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A076286
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Numbers of the form (7^{mr}-1)/(7^r-1) for positive integers m, r.
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8
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1, 8, 50, 57, 344, 400, 2402, 2451, 2801, 16808, 19608, 117650, 117993, 120100, 137257, 823544, 960800, 5764802, 5767203, 5884901, 6725601, 40353608, 40471600, 47079208, 282475250, 282492057, 288360150, 329554457, 1977326744, 2306881200, 13841287202
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OFFSET
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1,2
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LINKS
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MAPLE
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[1, seq(seq((7^(d+r)-1)/(7^r-1), r = sort(convert(numtheory:-divisors(d), list), `>`)), d=1..20)]; # Robert Israel, Aug 27 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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