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A052279
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Primes such that the sum of the factorials of the digits is a perfect square.
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3
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17, 41, 71, 211, 433, 457, 547, 1013, 1031, 1103, 1301, 1489, 2063, 3001, 3011, 4451, 5077, 5441, 5651, 5717, 6203, 6551, 7057, 7507, 7517, 8419, 8941, 10163, 10613, 10631, 16103, 16301, 20369, 20639, 20693, 20873, 20963, 21313, 21661, 23003, 23087, 23131
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[Prime[Range[3000]], IntegerQ[Sqrt[Total[IntegerDigits[#]!]]]&] (* Harvey P. Dale, Apr 11 2016 *)
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PROG
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(PARI) isok(n) = isprime(n) && (d = digits(n)) && issquare(sum(i=1, #d, d[i]!)); \\ Michel Marcus, Jan 06 2014
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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