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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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%I #9 Jul 09 2019 13:03:46

%S 2,5,7,17,23,41,47,53,67,73,97,103,113,151,157,163,173,179,197,199,

%T 223,227,251,257,263,281,293,313,349,353,389,431,439,449,457,461,479,

%U 499,503,557,577,587,593,619,659,673,709,733,829,853,857,983,997,1033

%N Primes p such that the sum of the decimal digits of p^4 is also a prime.

%e 2^4=16, 1+6=7. 5^4=625, 6+2+5=13. 7^4=2401, 2+4+0+1=7.

%t Select[Prime@ Range@ 180, PrimeQ@ Total@ IntegerDigits[#^4] &] (* _Michael De Vlieger_, Jul 08 2019 *)

%o (PARI) isok(p) = isprime(p) && isprime(sumdigits(p^4)); \\ _Michel Marcus_, Apr 09 2019

%Y Cf. A007953 (sumdigits), A030514 (primes^4).

%K nonn,base,easy

%O 1,1

%A _Salvatore Di Guida_, Apr 09 2019