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%I #23 Jul 06 2024 04:47:01
%S 5,7,19,43,379,1531,3067,24571,98299,100663291,6442450939,51539607547,
%T 844424930131963,13510798882111483,55340232221128654843,
%U 1947111321950560360698936123457531,133804471191183738849214309635890169035882491
%N Primes in the sequence of sums of alternating powers of 2.
%C Sum of reciprocals = 0.4224131591021966740339033736...
%C Primes in A079360. - _R. J. Mathar_, Dec 03 2014
%H Amiram Eldar, <a href="/A079361/b079361.txt">Table of n, a(n) for n = 1..29</a>
%o (PARI) /* Primes in the sequence of sums of alternating powers of 2 */ pseq(n) = { j=a=1; p=2; sr=0; while(j<=n, a = a + 2^(p); if(isprime(a),print1(a" "); sr+=1.0/a; ); a = a+2^(p-1); if(isprime(a),print1(a" "); sr+=1.0/a; ); p+=1; j+=2; ); print(); print(sr); }
%Y Cf. A079360.
%K nonn
%O 1,1
%A _Cino Hilliard_, Feb 15 2003
%E Offset changed by _Georg Fischer_, Sep 02 2022
%E a(16)-a(17) from _Amiram Eldar_, Jul 06 2024
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