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%I #10 Nov 17 2018 21:44:24
%S 2,5,10,25,36,44,65,67,138,149,176,212,279,1293,2367,2463,2707,3130,
%T 4150,4635
%N Numbers k such that (10's complement factorial of k) + 1 is prime.
%C Larger values not certified.
%C Some of the larger entries may only correspond to probable primes.
%e a(2)=5 because (10-5)*(10-4)*(10-3)*(10-2)*(10-1) + 1 = 15121 is prime.
%t f[n_] := 10^Length[IntegerDigits[n]] - n; p = 1; Do[p *= f[n]; If[PrimeQ[p + 1], Print[n]], {n, 4635}] (* _Ryan Propper_, May 20 2006 *)
%Y Cf. A110396.
%K more,nonn,base
%O 1,1
%A _Jason Earls_, Aug 01 2005
%E More terms from _Ryan Propper_, May 20 2006
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