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A077721
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Primes which can be expressed as sum of distinct powers of 7.
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10
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7, 2801, 17207, 19559, 120401, 134513, 134807, 137201, 840743, 842759, 842801, 941249, 943601, 958007, 958049, 958343, 960793, 5782001, 5784409, 5899307, 5899601, 5899657, 5901659, 6591089, 6607903, 6706393, 6708787, 6722801, 6722857, 6723193
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OFFSET
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1,1
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COMMENTS
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Primes whose base 7 representation contains only zeros and 1's.
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LINKS
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Robert Israel, Table of n, a(n) for n = 1..10000
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MAPLE
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pos := 0:for i from 1 to 4000 do b := convert(i, base, 2); s := sum(b[j]*7^(j-1), j=1..nops(b)): if(isprime(s)) then pos := pos+1:a[pos] := s:fi: od:seq(a[j], j=1..pos);
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MATHEMATICA
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Select[Prime[Range[10^6]], Max[IntegerDigits[#, 7]]<=1 &] (* Vincenzo Librandi, Sep 07 2018 *)
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CROSSREFS
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Cf. A020449, A000695, A033044, A077717, A077718, A077719, A077720, A077722, A077723.
Sequence in context: A234621 A195680 A203587 * A235464 A297029 A242851
Adjacent sequences: A077718 A077719 A077720 * A077722 A077723 A077724
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KEYWORD
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nonn
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AUTHOR
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Amarnath Murthy, Nov 19 2002
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EXTENSIONS
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More terms from Sascha Kurz, Jan 03 2003
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STATUS
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approved
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