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Primes that can be written in binary representation as concatenation of two primes: p and p-2. That is, primes representable as p * 2^L + p-2, where p and p-2 are primes, and L is the length of binary representation of p-2: L = A070939(p-2).
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%I #5 Nov 21 2013 15:20:41

%S 23,61,1021,139021,145177,222127,2645257,2706727,2928019,3050959,

%T 3997597,38695537,45086077,49903561,50247667,53688727,56294101,

%U 545636617,556450387,558023299,563331877,563921719,581616979,582993277,607570027,619956709,638045197,660262579

%N Primes that can be written in binary representation as concatenation of two primes: p and p-2. That is, primes representable as p * 2^L + p-2, where p and p-2 are primes, and L is the length of binary representation of p-2: L = A070939(p-2).

%C A subsequence of A232085.

%F a(n) = A232237(n) * 2^A070939(A232237(n)-2) + A232237(n)-2.

%Y Cf. A000040, A070939, A232085.

%K nonn,base,less

%O 1,1

%A _Alex Ratushnyak_, Nov 20 2013