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Numbers k such that k^3 + k^2 + 1 is prime.
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%I #20 Sep 08 2018 12:44:03

%S 1,2,3,5,8,9,11,12,23,24,26,30,35,42,44,45,47,53,56,57,62,66,68,69,71,

%T 74,86,87,89,92,101,111,120,122,123,125,140,143,147,152,170,177,179,

%U 180,191,192,195,198,203,209,219,224,230,234,239,243,245,246,254,255,263

%N Numbers k such that k^3 + k^2 + 1 is prime.

%H Harvey P. Dale, <a href="/A119863/b119863.txt">Table of n, a(n) for n = 1..1000</a>

%e 92^3 + 92^2 + 1 = 787153 (prime), so 92 is in the sequence.

%p a:=proc(n) if isprime(n^3+n^2+1)=true then n else fi end: seq(a(n),n=0..300); # _Emeric Deutsch_, Aug 04 2006

%t Select[Range[300],PrimeQ[#^3+#^2+1]&] (* _Harvey P. Dale_, May 03 2014 *)

%o (PARI) is(n)=isprime(n^3+n^2+1) \\ _Charles R Greathouse IV_, Jan 21 2015

%Y Cf. A005574.

%K nonn

%O 1,2

%A _Parthasarathy Nambi_, Jul 31 2006

%E More terms from _Emeric Deutsch_ and _R. J. Mathar_, Aug 04 2006