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%I #19 Jun 13 2017 10:34:13
%S 2,4,6,10,11,18,29,151,920,1456,1716,1915,4148,4403,8005,9600,41945,
%T 47238
%N Numbers n such that (23*10^n - 26)/6 is prime.
%e n = 2, 4, and 6, yield (23*10^n - 26)/6 = 379, 38329, and 3833329, respectively, which are prime.
%t fQ[n_] := PrimeQ[(23*10^n - 26)/6]; Select[ Range@ 10000, fQ] (* _Robert G. Wilson v_, Jan 28 2015 *)
%o (PARI) is(n)=ispseudoprime((23*10^n-26)/6) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A254005.
%K nonn,more
%O 1,1
%A _Hans Havermann_, Jan 24 2015