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A307452
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Primes p such that the sum of the decimal digits of p^4 is also a prime.
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0
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2, 5, 7, 17, 23, 41, 47, 53, 67, 73, 97, 103, 113, 151, 157, 163, 173, 179, 197, 199, 223, 227, 251, 257, 263, 281, 293, 313, 349, 353, 389, 431, 439, 449, 457, 461, 479, 499, 503, 557, 577, 587, 593, 619, 659, 673, 709, 733, 829, 853, 857, 983, 997, 1033
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OFFSET
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1,1
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LINKS
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EXAMPLE
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2^4=16, 1+6=7. 5^4=625, 6+2+5=13. 7^4=2401, 2+4+0+1=7.
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MATHEMATICA
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Select[Prime@ Range@ 180, PrimeQ@ Total@ IntegerDigits[#^4] &] (* Michael De Vlieger, Jul 08 2019 *)
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PROG
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(PARI) isok(p) = isprime(p) && isprime(sumdigits(p^4)); \\ Michel Marcus, Apr 09 2019
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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