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%I #37 Feb 25 2024 05:59:54
%S 73,733,739,967,1021,1103,1153,1223,1237,1453,1523,1657,1723,1741,
%T 1831,3023,3911,7057,7187,7523,7577,7643,7673,7699,7717,7841,9161,
%U 9173,9293,9497,9679,9749,9803,9833,9883,9923,9931,10151,10273,10453,10853,11003,11083,11243,11423
%N Primes that are non-Chen primes whose reversal is a Chen prime.
%C The second term of the sequence: 733 is congruent to 1 mod 61, to 2 mod 43, to 3 mod 73, where 61 is the second non-Chen prime, 43 is the first non-Chen prime and 73 is the third non-Chen prime. 733 is also congruent to 4 mod (3^6).
%t cpQ[n_] := Module[{rev = FromDigits[Reverse[IntegerDigits[n]]]}, PrimeOmega[n + 2] > 2 && PrimeQ[rev] && PrimeOmega[rev + 2] < 3]; Select[Prime[Range[1300]], cpQ] (* _Amiram Eldar_, Nov 09 2018 after _Harvey P. Dale_ at A118725 *)
%o (PARI) forprime(p=1,10^4,w=Vecrev(digits(p));q=0;for(j=1,length(w),q=q*10+w[j]);if(ispseudoprime(q)==1,if(bigomega(p+2)>2,if(bigomega(q+2)<=2,print1(p,", ")))))
%Y Cf. A109611, A102540.
%K nonn,base
%O 1,1
%A _Paolo Galliani_, Nov 09 2018
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