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A105180
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Numbers k such that 2^(2*k+1) + 2^k + 1 is prime.
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0
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1, 2, 3, 5, 9, 25, 34, 36, 42, 52, 176, 262, 269, 283, 284, 289, 372, 392, 486, 596, 999, 1022, 1097, 1105, 2329, 2663, 3037, 3363, 3853, 5167, 6305, 7164, 7283, 8874, 10974, 14450, 14763, 15016, 15320, 24869, 27192, 35164, 37595, 43540
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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2^3 + 2^1 + 1 = 11 prime so a(1) = 1.
2^5 + 2^2 + 1 = 37 prime so a(2) = 2.
2^7 + 2^3 + 1 = 137 prime so a(3) = 3.
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PROG
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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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EXTENSIONS
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STATUS
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approved
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