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Primes of the form prime(n) + n + n^2.
2

%I #32 Jan 08 2017 15:56:34

%S 17,41,73,113,139,163,193,223,491,859,919,1187,1259,1409,1483,1901,

%T 1987,2083,2267,2467,2677,3221,4339,4603,5923,6079,7573,8839,9421,

%U 9619,10223,11489,11701,12143,12589,13499,13729,14449,15679,16183,16703,17231,17497,19121

%N Primes of the form prime(n) + n + n^2.

%H Robert Israel, <a href="/A267421/b267421.txt">Table of n, a(n) for n = 1..10000</a>

%e The ninth prime is 23, and 23 + 9 + 9^2 = 113, which is prime, so 113 is in the sequence.

%p p:= 0: Res:= NULL:

%p for n from 1 to 1000 do

%p p:= nextprime(p);

%p if isprime(p+n+n^2) then Res:= Res, p+n+n^2 fi

%p od:

%p Res; # _Robert Israel_, Jan 08 2017

%t Select[Table[Prime[n] + n + n^2, {n, 100}], PrimeQ] (* _Alonso del Arte_, Feb 22 2016 *)

%o (PARI) lista(nn) = {for (n=1, nn, if (isprime(p=prime(n)+n+n^2), print1(p, ", ")););} \\ _Michel Marcus_, Mar 13 2016

%Y Cf. A014688, A128938.

%K nonn,easy

%O 1,1

%A _Emre APARI_, Jan 14 2016

%E More terms from _Michel Marcus_, Mar 13 2016