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Numbers n such that 3*n^2/2 - 1 is a prime.
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%I #8 Jul 03 2017 11:23:36

%S 2,4,6,10,14,16,20,24,26,34,40,44,54,56,60,64,70,76,86,90,104,110,116,

%T 120,124,126,130,136,140,146,150,154,164,166,174,186,194,200,204,230,

%U 240,244,260,264,286,300,306,336,346,354,374,386,394,400,414,416,420

%N Numbers n such that 3*n^2/2 - 1 is a prime.

%C All terms must be even numbers. - _Harvey P. Dale_, Jul 03 2017

%D M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988

%D Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta,UTET, CittaStudiEdizioni, Milano 1997

%t Select[Range[0,500,2],PrimeQ[(3#^2)/2-1]&] (* _Harvey P. Dale_, Jul 03 2017 *)

%o (PARI) forstep(n=2,1000,2, if(isprime(3*n^2/2-1), print1(n,", "))) - _Rick L. Shepherd_, May 06 2008

%Y Cf. A090686.

%K nonn

%O 1,1

%A _Giovanni Teofilatto_, Dec 22 2003

%E Corrected and extended by _Rick L. Shepherd_, May 06 2008