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 A124200 Numbers n such that 1 + n + n^3 + n^5 + n^7 + n^9 + n^11 + n^13 + n^15 + n^17 + n^19 + n^21 + n^23 + n^25 + n^27 + n^29 + n^31 + n^33 + n^35 + n^37 + n^39 + n^41 + n^43 is prime. 5
 1, 7, 10, 171, 304, 322, 357, 385, 418, 436, 448, 592, 606, 628, 642, 858, 1065, 1186, 1438, 1543, 1639, 1843, 1848, 1879, 1899, 2110, 2241, 2517, 2544, 2578, 2668, 3195, 3207, 3306, 3307, 3657, 4137, 4177, 4329, 4617, 4837, 4945, 4956, 5026, 5281, 5509 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..620 MATHEMATICA Do[If[PrimeQ[1 + n + n^3 + n^5 + n^7 + n^9 + n^11 + n^13 + n^15 + n^17 + n^19 + n^21 + n^23 + n^25 + n^27 + n^29 + n^31 + n^33 + n^35 + n^37 + n^39 + n^41 + n^43], Print[n]], {n, 1, 2400}] Select[Range[6000], PrimeQ[Total[#^Range[1, 43, 2]] + 1] &] (* Vincenzo Librandi, Jun 28 2014 *) PROG (MAGMA) [n: n in [0..5000] | IsPrime(s) where s is 1+&+[n^i: i in [1..43 by 2]]]; // Vincenzo Librandi, Jun 28 2014 (PARI) is(n)=isprime(1+n+n^3+n^5+n^7+n^9+n^11+n^13+n^15+n^17+n^19+n^21+n^23 + n^25+n^27+n^29+n^31+n^33+n^35+n^37+n^39+n^41+n^43) \\ Charles R Greathouse IV, Feb 20 2017 CROSSREFS Cf. A049407, similar sequences listed in A244376. Sequence in context: A136865 A123797 A123805 * A282038 A133346 A091920 Adjacent sequences:  A124197 A124198 A124199 * A124201 A124202 A124203 KEYWORD nonn,easy AUTHOR Artur Jasinski, Dec 13 2006 STATUS approved

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Last modified February 24 17:29 EST 2020. Contains 332209 sequences. (Running on oeis4.)