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A199192
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Primes of the form 3^(2n-3)+3^(n-1)+1.
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2
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7, 37, 271, 2269, 19927, 129159847, 1162320517, 49269609804781974450852068861184694669, 589881151426658740854227725580736348850640632297373414091790995505756623268837
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OFFSET
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1,1
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COMMENTS
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The corresponding n are in A199191.
The next term -- a(10) -- has 152 digits. - Harvey P. Dale, May 28 2015
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LINKS
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FORMULA
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MATHEMATICA
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a={}; Do[p=( (3^(n-1) + 1)^3 -1)/3^n; If[PrimeQ[p], AppendTo[a, p]], {n, 10^2}]; Print[a];
Select[Table[3^(2n-3)+3^(n-1)+1, {n, 100}], PrimeQ] (* Harvey P. Dale, May 28 2015 *)
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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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