%I #22 May 28 2021 17:43:37
%S 3,5,7,9,15,17,25,41,63,79,91,103,299,341,431,445,465,519,1251,2469,
%T 2507,2549,6817,8519,18983,38715
%N Numbers k such that k!! + 2^3 is prime.
%C a(27) > 50000. - _Robert Price_, Jan 06 2015
%H Henri & Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=n%212%2B2%5E3">PRP Records.</a>
%H OpenPFGW Project, <a href="http://www.primeform.net/openpfgw/">Primality Tester</a>
%t lst={}; Do[If[PrimeQ[n!!+2^3], AppendTo[lst, n]], {n, 0, 50000}]; lst
%t Select[Range[40000],PrimeQ[#!!+8]&] (* _Harvey P. Dale_, May 28 2021 *)
%Y Cf. A006882, A080778 and A076185, A076186, A076189, A076190, A076193, A076194, A076195, A076196, A076197 for other values of s in n!!+2^s.
%K nonn,more
%O 1,1
%A _Zak Seidov_, Nov 02 2002
%E Edited and extended (n<4096) by _Hugo Pfoertner_, Jun 19 2003
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
%E a(25) from _Robert Price_, Nov 01 2012
%E a(26) from _Robert Price_, Jan 06 2015
|