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A121089
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Numbers n such that f(n), f(n+1) and f(n+2) are prime, f(m)=72*m^2+7.
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1
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9, 24, 169, 1479, 2964, 3039, 3299, 4084, 4474, 5534, 5574, 6449, 7359, 7409, 7529, 10789, 10879, 10994, 13819, 14324, 18574, 19709, 20329, 20749, 22179, 24529, 25089, 25104, 25229, 25404, 27714, 27779, 29849, 30234, 32369, 33384, 34799
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OFFSET
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1,1
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COMMENTS
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Apparently there are no four subsequent numbers m with f(m) prime.
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LINKS
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MATHEMATICA
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Reap[Do[If[PrimeQ[72*n^2+7]&&PrimeQ[72*(n+1)^2+7]&&PrimeQ[72*(n+2)^2+7], Sow[n]], {n, 0, 300000}]][[2, 1]]
Flatten[Position[Partition[Table[PrimeQ[72n^2+7], {n, 35000}], 3, 1], {True, True, True}]] (* Harvey P. Dale, Aug 17 2014 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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