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%I #16 Feb 16 2020 00:46:59
%S 11,12,14,16,20,22,26,28,29,30,32,34,38,40,44,46,50,52,56,58,62,64,68,
%T 70,74,76,80,82,83,84,86,88,92,94,98,100,104,106,110,112,116,118,122,
%U 124,128,130,134,136,140,142,146,148,152,154,158,160,164,166,170,172,176,178,182,184,188,190,194,200
%N Numbers of the form 3^k + prime, with k > 1.
%H Alois P. Heinz, <a href="/A332379/b332379.txt">Table of n, a(n) for n = 1..10000</a>
%H Christian Elsholtz, Florian Luca, and Stefan Planitzer, <a href="https://doi.org/10.1007/s11139-017-9972-8">Romanov type problems</a>, The Ramanujan Journal 47.2 (2018): 267-289.
%p q:= n-> ormap(k-> isprime(n-3^k), [$2..ilog[3](n)]):
%p select(q, [$1..200])[]; # _Alois P. Heinz_, Feb 14 2020
%Y Cf. A218044.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Feb 14 2020