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Numbers n such that 3n + 5 is a prime.
10

%I #19 Jun 08 2020 10:02:25

%S -1,0,2,4,6,8,12,14,16,18,22,26,28,32,34,36,42,44,48,54,56,58,62,64,

%T 74,76,78,82,84,86,88,92,96,102,104,114,116,118,126,128,132,138,142,

%U 146,148,152,154,158,162,166,168,172,184,186,188,194,196,198,204,212,214,216,218

%N Numbers n such that 3n + 5 is a prime.

%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

%H Harvey P. Dale, <a href="/A088879/b088879.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A024893(n) - 1 = A087370(n) - 2.

%t lst={};Do[p=n+(n+2)+(n+3);If[PrimeQ[p],AppendTo[lst,n]],{n,0,5!}];lst (* _Vladimir Joseph Stephan Orlovsky_, May 22 2009 *)

%t Select[Range[-1,300],PrimeQ[3#+5]&] (* _Harvey P. Dale_, Jun 08 2020 *)

%Y A003627 gives primes, A091177 gives prime index.

%Y Cf. A016789.

%K easy,sign

%O 1,3

%A _Giovanni Teofilatto_, Nov 27 2003

%E Edited and extended by _Ray Chandler_, Dec 26 2003