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%I #9 Feb 20 2018 22:51:14
%S 0,12,62,121,126,205,241,877,1021,1022,1645,2041,2424,2761,2791,2965,
%T 3355,3445,3541,4021,4081,4094,4165,4825,5071,5191,5251,5593,6151,
%U 6385,6631,7465,7765,7884,8137,8188
%N Numbers n such that A294386(n) = 2^(k-1)*(2^k - 2*n - 1) for some k such that 2^k - 2*n - 1 is prime.
%e a(3) = 62 is in the sequence because A294386(62) = 192 = 2^6*3 where 2^7 - 2*62 - 1 = 3 is prime.
%p # Assuming A294386[n] has been assigned for n from 0 to N
%p Res:= NULL:
%p for n from 0 to N do
%p for k from ilog2(2*n+1)+1 do
%p p:= 2^k - 2*n-1;
%p if 2^(k-1)*p > A294386[n] then break fi;
%p if isprime(p) then
%p if A294386[n] = 2^(k-1)*p then Res:= Res, n fi;
%p break
%p fi
%p od
%p od:
%p Res;
%Y Cf. A096502, A294386.
%K nonn,more
%O 1,2
%A _Robert Israel_, Nov 06 2017
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