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A344384
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Prime numbers p such that p-1 or p+1 is a number of least prime signature (A025487).
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3
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2, 3, 5, 7, 11, 13, 17, 23, 29, 31, 37, 47, 59, 61, 71, 73, 97, 127, 179, 181, 191, 193, 211, 239, 241, 257, 359, 383, 419, 421, 431, 433, 479, 577, 719, 769, 839, 863, 1151, 1153, 1259, 1297, 1439, 1801, 2161, 2309, 2311, 2521, 2591, 2593, 2879, 3359, 3361
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OFFSET
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1,1
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COMMENTS
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The corresponding numbers of least prime signature are A344385.
19 is the first prime not in this sequence.
Questions: 1) Is this sequence infinite? 2) Is log(a(n)) = O(log(n)^2)?
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LINKS
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EXAMPLE
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17 is a term because 17 - 1 = 16 is a number of least prime signature.
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MATHEMATICA
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{2}~Join~Select[Prime@ Range[2, 900], AnyTrue[# + {-1, 1}, Times @@ MapIndexed[Prime[First[#2]]^#1 &, Sort[FactorInteger[#][[All, -1]], Greater] ] == # &] &] (* Michael De Vlieger, May 16 2021 *)
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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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