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A080131
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Conjectured number of generalized Fermat primes of the form (n+1)^2^k + n^2^k, with k>1.
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4
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3, 1, 2, 1, 2, 2, 1, 2, 1, 1, 0, 2, 1, 2, 0, 1
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OFFSET
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1,1
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COMMENTS
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Primes that are the sum of consecutive integers (k=0) and consecutive squares (k=1) are excluded. Values of k <= 16 were tested. The sequence A078902 lists some of the generalized Fermat primes. Bjorn and Riesel examined generalized Fermat numbers for n <= 11 and k <= 999.
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LINKS
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EXAMPLE
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a(1) = 3 because there are three Fermat primes (with k>1): 17, 257, 65537.
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MATHEMATICA
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lst={}; Do[prms=0; Do[If[PrimeQ[(n+1)^2^k+n^2^k], prms++ ], {k, 2, 16}]; AppendTo[lst, prms], {n, 16}]; lst
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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STATUS
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approved
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