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%I #23 Mar 22 2018 10:03:20
%S 1,2,3,4,5,7,12,19,23,45,58,149,151,197,682,879,1134,1906,6616,10242
%N Numbers k such that k*k! + 1 is prime.
%F a(n) = A049432(n)-1.
%e 3*3!+1 = 19 and 19 is prime, so 3 is a member.
%t Do[If[PrimeQ[n*n! + 1], Print[n]], {n, 0, 2000}] (* Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), May 05 2006 *)
%o (PARI) isok(k) = ispseudoprime(k*k! + 1); \\ _Altug Alkan_, Mar 22 2018
%Y Cf. A049432.
%K nonn,more
%O 1,2
%A mohammed bouayoun (bouyao(AT)wanadoo.fr), Jan 15 2004
%E a(17) from Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), May 05 2006
%E a(18)-a(19) from _Jason Earls_, Jan 24 2008
%E a(20) from _Seiichi Manyama_ (by using the data calculated by _Donovan Johnson_, Dec 18 2009), Mar 22 2018
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