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%I #15 Jul 23 2023 06:06:50
%S 11,1011,101011,1010101011,101010101011,1010101010101011,
%T 101010101010101011,1010101010101010101011,
%U 101010101010101010101010101011,101010101010101010101010101010101010101011
%N Binary expansion of A000979(n).
%H Amiram Eldar, <a href="/A127962/b127962.txt">Table of n, a(n) for n = 1..20</a>
%F a(n) = A007088(A000979(n)). - _Amiram Eldar_, Jul 23 2023
%t b[n_] := FromDigits[IntegerDigits[n, 2]]; b /@ Select[Table[(2^p + 1)/3, {p, Prime[Range[15]]}], PrimeQ] (* _Amiram Eldar_, Jul 23 2023 *)
%o (Python)
%o from gmpy2 import divexact
%o from sympy import prime, isprime
%o A127962 = [int(bin(p)[2:]) for p in (divexact(2**prime(n)+1,3) for n in range(2,10**2)) if isprime(p)] # _Chai Wah Wu_, Sep 04 2014
%Y Cf. A000978, A000979, A007088, A124400, A126614, A127936, A127955, A127956, A127957, A127958, A127961.
%K nonn,base
%O 1,1
%A _Artur Jasinski_, Feb 09 2007
%E Edited by _N. J. A. Sloane_, Jun 11 2007