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Search: id:A133320
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| A133320 |
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Numbers n such that both A124296(n) = 5*F(n)^2 - 5*F(n) + 1 and A124297(n) = 5*F(n)^2 + 5*F(n) + 1 are prime, where F(n) = Fibonacci[n]. |
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OFFSET
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1,1
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MATHEMATICA
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Do[ F=Fibonacci[n]; f=5*F^2-5*F+1; g=5*F^2+5*F+1; If[ PrimeQ[f], If[ PrimeQ[g], Print[ {n, f, g} ] ] ], {n, 1, 1000} ]
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CROSSREFS
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Cf. A124297 = 5*F(n)^2 + 5*F(n) + 1, where F(n) = Fibonacci[n]. Cf. A124296 = 5*F(n)^2 - 5*F(n) + 1, where F(n) = Fibonacci[n]. Cf. A000032, A000045, A121171, A001946.
Sequence in context: A122413 A136366 A123820 this_sequence A128920 A006288 A047598
Adjacent sequences: A133317 A133318 A133319 this_sequence A133321 A133322 A133323
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KEYWORD
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more,nonn
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AUTHOR
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Alexander Adamchuk (alex(AT)kolmogorov.com), Oct 18 2007
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