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%I #20 May 24 2017 06:46:33
%S 5,6,8,14,16,20,22,26,32,40,46,50,56,70,110,140,260,470,1190,1330
%N n - 3^k is a prime for all k > 0 such that 3^k < n.
%C Is the sequence finite?
%C No other terms below 3^36. - _Max Alekseyev_, Dec 12 2011
%e 40 is a member as 40 - 3 = 37, 40 - 9 = 31, 40 - 27 = 13 are all primes.
%t A067527 = {}; Do[k = 1; While[p = n - 3^k; p > 0 && PrimeQ[p], k++]; If[p <= 0, AppendTo[A067527, n]], {n, 4, 10000}]; A067527 (* _T. D. Noe_, Feb 20 2005 *)
%Y Cf. A067526.
%Y Cf. A039669 (n - 2^k is prime).
%K nonn,hard,more
%O 1,1
%A _Amarnath Murthy_, Feb 17 2002
%E More terms from _Sascha Kurz_, Mar 18 2002
%E Edited by _Max Alekseyev_, Dec 12 2011