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%I #2 Mar 30 2012 17:36:44
%S 1,2,4,23,76,339,1282
%N Numbers n such that primorial(n)^4 + 1 is prime.
%C Seven terms found and primes proved by PrimeForm ([N-1, Brillhart-Lehmer-Selfridge]). p(1282)#^4 + 1 has 18042 decimal digits. There are no more terms <= 2810.
%e As primorial(2)^4 + 1 = (3*2)^4 + 1 = 1297 is prime, 2 is a term.
%Y Cf. A092061.
%K hard,nonn
%O 1,2
%A _Rick L. Shepherd_, Sep 26 2007
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