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Numbers k such that (the sum of digits of k!)+1 is a prime.
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%I #17 Dec 04 2024 23:05:17

%S 0,1,2,3,4,11,22,25,27,29,32,38,43,51,57,62,72,74,75,77,81,83,92,102,

%T 117,118,122,128,143,148,151,152,154,165,177,186,188,191,193,196,205,

%U 209,210,213,221,227,230,234,235,247,262,274,282,298,300,301,307,310

%N Numbers k such that (the sum of digits of k!)+1 is a prime.

%H Harry J. Smith, <a href="/A066347/b066347.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[0,400],PrimeQ[Total[IntegerDigits[#!]]+1]&] (* _Harvey P. Dale_, Jan 27 2023 *)

%o (PARI) isok(k) = {isprime(sumdigits(k!) + 1)} \\ _Harry J. Smith_, Feb 11 2010

%K base,nonn

%O 1,3

%A _Jason Earls_, Dec 19 2001

%E Definition clarified by _Harvey P. Dale_, Jan 27 2023