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Numbers n such that the absolute value of (n - sum of the factorials of its digits) is prime.
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%I #5 Dec 15 2017 17:36:51

%S 3,14,20,24,25,30,37,43,50,53,59,60,67,73,79,80,97,100,105,110,115,

%T 124,125,134,138,146,151,152,158,171,172,198,201,202,225,227,235,243,

%U 249,250,255,259,260,265,295,301,302,306,314,318,320,325,327,330,343,347

%N Numbers n such that the absolute value of (n - sum of the factorials of its digits) is prime.

%C 6*10^843-1 generates an 844-digit prime.

%H Harvey P. Dale, <a href="/A108933/b108933.txt">Table of n, a(n) for n = 1..1000</a>

%e a(5)=25 because |25-(2!+5!)| = 97, a prime.

%t Select[Range[400],PrimeQ[Abs[#-Total[IntegerDigits[#]!]]]&] (* _Harvey P. Dale_, Oct 03 2017 *)

%Y Cf. A108911.

%K base,easy,nonn

%O 1,1

%A _Jason Earls_, Jul 20 2005