%I A088054
%S A088054 2,3,5,7,23,719,5039,39916801,479001599,87178291199,
%T A088054 10888869450418352160768000001,265252859812191058636308479999999,
%U A088054 263130836933693530167218012159999999,8683317618811886495518194401279999999
%N A088054 Factorial primes: primes which are within 1 of a factorial number.
%C A088054 Conjecture: 3 is the intersection of A002981 and A002982).
%H A088054 Wikipedia, <a href="http://en.wikipedia.org/wiki/Factorial_prime">Factorial
prime</a>.
%e A088054 3!+1=7; 7!-1=5039
%e A088054 39916801 is a term because 11!+1 is prime.
%t A088054 t = {}; Do[ If[PrimeQ[n! - 1], AppendTo[t, n! - 1]]; If[PrimeQ[n! + 1],
AppendTo[t, n! + 1]], {n, 50}]; t (* Robert G. Wilson v *)
%t A088054 Union[Select[Range[50]!-1, PrimeQ], Select[Range[50]!+1, PrimeQ]] (Noe)
%Y A088054 Cf. A000142, A002981, A002982.
%Y A088054 Union of A055490 and A088332.
%Y A088054 Sequence in context: A062088 A070029 A110094 this_sequence A085907 A024777
A002957
%Y A088054 Adjacent sequences: A088051 A088052 A088053 this_sequence A088055 A088056
A088057
%K A088054 easy,nice,nonn
%O A088054 1,1
%A A088054 Christopher M. Tomaszewski (cmt1288(AT)comcast.net), Nov 02 2003
%E A088054 Corrected by Paul Muljadi (paulmuljadi(AT)yahoo.com), Oct 11 2005
%E A088054 More terms from Robert G. Wilson v (rgwv(at)rgwv.com) and T. D. Noe (noe(AT)sspectra.com),
Oct 12 2005
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