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A279882
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a(n) = 2^(prime(n) + 1) - 1.
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1
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7, 15, 63, 255, 4095, 16383, 262143, 1048575, 16777215, 1073741823, 4294967295, 274877906943, 4398046511103, 17592186044415, 281474976710655, 18014398509481983, 1152921504606846975, 4611686018427387903, 295147905179352825855, 4722366482869645213695
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OFFSET
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1,1
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COMMENTS
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Numbers whose binary representation is 1 repeated (prime(n)+1) times.
The only prime term is 7.
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LINKS
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FORMULA
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EXAMPLE
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For n=3; a(3) = 2^(prime(3) + 1) - 1 = 2^(5 + 1) - 1 = 2^6 - 1 = 63.
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MAPLE
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MATHEMATICA
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PROG
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(Magma) [2^(NthPrime(n)+1)-1: n in[1..50]]
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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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STATUS
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approved
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