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A344781
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Numbers k such that A070313(k) = 2^k - (2*k+1) is a prime number.
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1
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4, 7, 8, 28, 32, 81, 669, 1108, 1699, 1839, 2319, 9566, 14866, 30855, 35932
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OFFSET
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1,1
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COMMENTS
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The corresponding primes are 7, 113, 239, 268435399, 4294967231, 2417851639229258349412189, ...
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LINKS
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EXAMPLE
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4 is a term since 2^4 - (2*4+1) = 16 - 9 = 7 is a prime.
7 is a term since 2^7 - (2*7+1) = 128 - 15 = 113 is a prime.
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MATHEMATICA
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Select[Range[2400], PrimeQ[2^# - 2*# - 1] &]
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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