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%I #32 Jul 20 2019 08:07:21
%S 5,7,21,33,153,167,171,391,789,1323,2645,8655,10153,39967,45369,47599
%N Numbers k such that k!! + 2^10 is prime.
%C a(17) > 50000. - _Robert Price_, Feb 24 2015
%H Henri & Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=n%212%2B2%5E10&action=Search">PRP Records.</a>
%H OpenPFGW Project, <a href="http://www.primeform.net/openpfgw/">Primality Tester</a>
%t lst={};Do[If[PrimeQ[n!!+2^10], (*Print[n];*)AppendTo[lst, n]], {n, 6!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Aug 26 2008 *)
%o (Python)
%o from gmpy2 import is_prime
%o A076197_list, g, h = [], 1, 1024
%o for i in range(3,10**5,2):
%o ....g *= i
%o ....if is_prime(g+h):
%o ........A076197_list.append(i) # _Chai Wah Wu_, May 31 2015
%Y Cf. A006882.
%Y Numbers k such that k!! + 2^s is prime: A080778 (s=0), A076185 (s=1), A076186 (s=2), A076188 (s=3), A076189 (s=4), A076190 (s=5), A076193 (s=6), A076194 (s=7), A076195 (s=8), A076196 (s=9).
%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 8655 from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
%E a(13) from _Robert Price_, Mar 10 2013
%E a(14)-a(16) from _Robert Price_, Feb 24 2015
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