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%I #15 Jul 20 2019 08:08:33
%S 12,20,36,38,40,46,52,56,58,60,62,64,74,78,80,86,88,112,118,120,122,
%T 124,128,132,134,136,138,140,142,146,156,160,162,164,166,170,176,182,
%U 184,186,188,190,194,198,208,210,212,216
%N Even numbers k such that prime(k) -+ k are both composite.
%C Even numbers not in A064269 and not in A064402.
%C Interestingly, prime(12) = 37 and both 37 - 12 = 25 and 37 + 12 = 49 are squares. Is there another such n?
%t Select[2*Range[200],!PrimeQ[Prime[#]+#]&&!PrimeQ[Prime[#]-#]&] (* _Harvey P. Dale_, Dec 24 2013 *)
%o (PARI) {forstep(i=2,220,2,p=prime(i);if(!isprime(p-i)&&!isprime(p+i),print1(i", ")))}
%Y Cf. A064269, A064402.
%K nonn
%O 1,1
%A _Zak Seidov_, Jan 04 2013