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a(1)=1, a(n) is the smallest power of 2 not included earlier such that Sum_{k=1..n} a(k) is prime.
3

%I #14 Dec 28 2024 10:19:26

%S 1,2,4,16,8,4096,32,16384,134217728,256,33554432,1073741824,

%T 2147483648,68719476736,8192,262144,

%U 2722258935367507707706996859454145691648,1152921504606846976,10889035741470030830827987437816582766592

%N a(1)=1, a(n) is the smallest power of 2 not included earlier such that Sum_{k=1..n} a(k) is prime.

%F Conjecture: a(n) = A059661(n)-A059661(n-1). - _R. J. Mathar_, May 07 2007

%Y Cf. A059661.

%K nonn,changed

%O 1,2

%A _Amarnath Murthy_, Aug 19 2002

%E More terms from _Benoit Cloitre_, Aug 27 2002

%E Name corrected by _Sean A. Irvine_, Dec 28 2024