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A077717
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Primes which can be expressed as a sum of distinct powers of 3.
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11
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3, 13, 31, 37, 109, 271, 283, 337, 733, 739, 757, 769, 811, 823, 1009, 1063, 1093, 2269, 2281, 2467, 2521, 2539, 2551, 2917, 2953, 3001, 3037, 3163, 3169, 3187, 3253, 3271, 6571, 6673, 6679, 6841, 7321, 7411, 7537, 7561, 7573, 8761, 8779, 8839, 9001
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OFFSET
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1,1
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COMMENTS
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Primes whose base 3 representation contains only 0's and 1's.
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LINKS
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EXAMPLE
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31 = 3^3 + 3 + 1 belongs to this sequence.
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MATHEMATICA
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Select[FromDigits[#, 3]&/@Tuples[{0, 1}, 10], PrimeQ] (* Harvey P. Dale, Mar 30 2015 *)
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PROG
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(PARI) print1(3); forstep(n=3, 1e3, 2, if(isprime(t=fromdigits(binary(n), 3)), print1(", "t))) \\ Charles R Greathouse IV, Mar 28 2022
(PARI) is_A077717(n)=vecmax(digits(n, 3))<2 && isprime(n)
(Python)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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