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Primes such that the sum of the factorials of the digits is a perfect square.
3

%I #12 Apr 11 2016 15:45:11

%S 17,41,71,211,433,457,547,1013,1031,1103,1301,1489,2063,3001,3011,

%T 4451,5077,5441,5651,5717,6203,6551,7057,7507,7517,8419,8941,10163,

%U 10613,10631,16103,16301,20369,20639,20693,20873,20963,21313,21661,23003,23087,23131

%N Primes such that the sum of the factorials of the digits is a perfect square.

%H Giovanni Resta, <a href="/A052279/b052279.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Prime[Range[3000]],IntegerQ[Sqrt[Total[IntegerDigits[#]!]]]&] (* _Harvey P. Dale_, Apr 11 2016 *)

%o (PARI) isok(n) = isprime(n) && (d = digits(n)) && issquare(sum(i=1, #d, d[i]!)); \\ _Michel Marcus_, Jan 06 2014

%Y Cf. A000040, A000142, A000290, A061602.

%K base,nonn

%O 1,1

%A _G. L. Honaker, Jr._, Feb 05 2000

%E More terms from _Michel Marcus_, Jan 06 2014