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%I #22 Sep 08 2022 08:45:28
%S 1,3,69,86,104,110,138,146,210,238,247,260,264,269,316,436,572,600,
%T 621,654,666,715,737,740,744,754,779,1056,1156,1159,1216,1218,1221,
%U 1343,1419,1434,1442,1524,1580,1603,1676,1680,1731,1742,1804,1952,1956,1985
%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 is prime.
%H Vincenzo Librandi, <a href="/A124181/b124181.txt">Table of n, a(n) for n = 1..1390</a>
%F 1 together with numbers n such that (n^25-n)/(n^2-1) + 1 is prime. - _Charles R Greathouse IV_, Jul 02 2013
%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], Print[n]], {n, 1, 1400}]
%t Select[Range[3000], PrimeQ[Total[#^Range[1, 23, 2]] + 1] &] (* _Vincenzo Librandi_, Jun 28 2014 *)
%o (PARI) is(n)=n==1 || isprime((n^25-n)/(n^2-1)+1) \\ _Charles R Greathouse IV_, Jul 02 2013
%o (Sage)
%o i,n = var('i,n')
%o [n for n in (1..2000) if is_prime(1+(n^(2*i+1)).sum(i,0,11))] # _Bruno Berselli_, Jun 27 2014
%o (Magma) [n: n in [0..2000] | IsPrime(s) where s is 1+&+[n^i: i in [1..23 by 2]]]; // _Vincenzo Librandi_, Jun 28 2014
%Y Cf. A049407, similar sequences listed in A244376.
%K nonn,easy
%O 1,2
%A _Artur Jasinski_, Dec 13 2006
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