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A124185 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 is prime. 5

%I

%S 182,219,393,468,629,638,755,824,960,965,984,1002,1053,1068,1095,1110,

%T 1140,1209,1233,1269,1457,1518,1539,1547,1590,1622,1659,1707,1797,

%U 1818,2174,2259,2333,2799,2975,3032,3074,3272,3285,3338,3368,3477,3564,4118

%N 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 is prime.

%H Vincenzo Librandi, <a href="/A124185/b124185.txt">Table of n, a(n) for n = 1..850</a>

%t 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], Print[n]], {n, 1, 1400}]

%t Select[Range[5000], PrimeQ[Total[#^Range[1, 27, 2]] + 1] &] (* _Vincenzo Librandi_, Jun 28 2014 *)

%o (MAGMA) [n: n in [0..5000] | IsPrime(s) where s is 1+&+[n^i: i in [1..27 by 2]]]; // _Vincenzo Librandi_, Jun 28 2014

%o (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) \\ _Charles R Greathouse IV_, Feb 20 2017

%Y Cf. A049407, similar sequences listed in A244376.

%K nonn,easy

%O 1,1

%A _Artur Jasinski_, Dec 13 2006

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Last modified November 22 08:46 EST 2019. Contains 329389 sequences. (Running on oeis4.)