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%I #12 Sep 08 2022 08:45:50
%S 1,2,4,6,10,28,30,42,52,58,66,88,108,136,156,172,196,238,312,346,352,
%T 388,448,520,546,556,570,576,598,612,646,676,732,742,786,856,906,940,
%U 976,1050,1068,1092,1152,1192,1222,1228,1236,1302,1432,1452,1458,1480
%N Numbers n such that n+1 is prime, and (n+1)^3-n^3 is prime.
%H Vincenzo Librandi, <a href="/A171447/b171447.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A165682(n)-1. - R. J. Mathar, Jan 04 2011
%e for n=10, 10+1=11 and 11^3-10^3=331; n=28, 28+1=29 and 29^3-28^3=2437
%t Select[Range[1500], PrimeQ[# + 1]&&PrimeQ[(# + 1)^3 - #^3]&] (* _Vincenzo Librandi_, Apr 05 2013 *)
%o (Magma) [n: n in [1..1500] | IsPrime(n+1) and IsPrime( (n+1)^3-n^3)]; // _Vincenzo Librandi_, Apr 05 2013
%o (PARI) is(n)=isprime(n+1) && isprime(3*n^3+3*n+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A165682.
%K nonn,easy
%O 1,2
%A _Vincenzo Librandi_, Dec 09 2009
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