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%I #8 Dec 09 2020 20:47:33
%S 0,1,3,9,33,107,333,1036,3153,9583,29010,87557,263679,793061,2383280,
%T 7158069,21490605,64504548,193579176,580868607,1742867913,5229128045,
%U 15688432647,47067395121,141206379612,423627527495,1270899359726,3812731633623,11438262009764
%N (nextprime(3^n)-nextprime(2^n))/2.
%F a(n) = A037128(n) / 2. - _Sean A. Irvine_, Dec 09 2020
%t Table[(NextPrime[3^n]-NextPrime[2^n])/2,{n,0,30}] (* _Harvey P. Dale_, Jun 08 2014 *)
%K nonn
%O 0,3
%A _N. J. A. Sloane_.
%E More terms from _Sean A. Irvine_, Dec 09 2020