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A161470
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Primes of the form 3^k+2^k+k^3-k^2.
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2
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OFFSET
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1,1
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COMMENTS
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The associated k are 1, 2, 3, 7, 13, 27, 73, 994, 1129, ... - R. J. Mathar, Jun 12 2009
The next term has 475 digits. - Harvey P. Dale, Dec 12 2010
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LINKS
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Table of n, a(n) for n=1..7.
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MATHEMATICA
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A161470 = {}; Do[If[PrimeQ[p = (3^n + 2^n) + (n^3 - n^2)], AppendTo[A161470, p]], {n, 6!}]; A161470 (* Orlovsky *)
(* Alternate: *) Select[Table[3^k + 2^k + k^3 - k^2, {k, 2000}], PrimeQ] (* Harvey P. Dale, Dec 12 2010 *)
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PROG
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(Magma) [ a: n in [1..450] | IsPrime(a) where a is 3^n+2^n+n^3-n^2] // Vincenzo Librandi, Nov 30 2010
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CROSSREFS
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Cf. A058765, A082101, A161469.
Sequence in context: A149656 A146063 A146006 * A295163 A195689 A079363
Adjacent sequences: A161467 A161468 A161469 * A161471 A161472 A161473
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KEYWORD
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nonn
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AUTHOR
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Vladimir Joseph Stephan Orlovsky, Jun 10 2009
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EXTENSIONS
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Definition simplified by R. J. Mathar, Jun 12 2009
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STATUS
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approved
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