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A050920
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Cullen primes: primes of the form n*2^n+1.
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6
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OFFSET
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1,1
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COMMENTS
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The next term is too large to display here, having 1423 digits. See A005849.
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LINKS
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FORMULA
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EXAMPLE
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1 * 2^1 + 1 = 3, which is prime.
141 * 2^141 + 1 = 393050634124102232869567034555427371542904833, which is also prime.
The third Cullen prime is approximately 2.677114856136697933736444 * 10^1422.
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MATHEMATICA
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Select[Table[n * 2^n + 1, {n, 5000}], PrimeQ] (* Harvey P. Dale, Dec 14 2014 *)
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CROSSREFS
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See A005849 for the corresponding n.
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KEYWORD
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nonn,nice,bref
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AUTHOR
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STATUS
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approved
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