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%I #26 Apr 28 2021 01:31:16
%S 2,3,5,7,23,29,41,43,47,61,67,83,89,131,137,139,157,173,179,191,197,
%T 223,227,229,241,263,269,283,311,313,317,337,353,359,373,379,397,401,
%U 409,421,443,449,463,467,487,557
%N Primes p where p + sumOfDigits(p) +- 3 is prime.
%C a(n) = A068690(n), A030144(n), A069556(n), A091727(n), A156756(n) if n<14.
%H Andrew Howroyd, <a href="/A225659/b225659.txt">Table of n, a(n) for n = 1..394</a>
%e If p = 409, then 409 + sod(409) +- 3 = 409+13 - 3 = 419, which is prime.
%e If p = 23, then 23 + sod(23) +- 3 = 23+5 + 3 = 31, which is prime.
%t Select[Prime[Range[102]],Or@@PrimeQ[#+Total[IntegerDigits[#]]+{3,-3}] &] (* _Jayanta Basu_, May 23 2013 *)
%o (PARI)
%o ok(p)= {my(s=vecsum(digits(p)));isprime(p) && (isprime(p+s-3) || isprime(p+s+3))}
%o select(ok,[1..1000]) \\ _Andrew Howroyd_, Feb 22 2018
%Y Cf. A000040, A007605, A068690, A030144, A069556, A091727, A156756.
%K nonn,easy,base,dumb
%O 1,1
%A _John-Å. W. Olsen_, May 11 2013