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%I #13 Oct 23 2022 10:28:11
%S 2,111,212,1011,1101,1121,2012,2122,10121,10211,11001,11201,12011,
%T 12121,12211,20012,20102,20122,21002,21022,22102,22122,22212,101001,
%U 101021,101111,102101,102121,110021,110111,110221,111121,111211,112001,112201,120011,120121
%N Not necessarily palindromic primes of which initial and terminal digits are identical, as written in base 3.
%C Base-3 analog of what A077652 is for base 10.
%H Harvey P. Dale, <a href="/A231278/b231278.txt">Table of n, a(n) for n = 1..2500</a>
%e a(3) = 212, which starts and ends with "2", and in base 3 means 2*(3^2) + 1*(3^1) + 2*(3^0) = 18 + 3 + 2 = 23 (base 10), which is prime.
%t FromDigits/@Select[IntegerDigits[#,3]&/@Prime[Range[100]],#[[1]]==#[[-1]]&] (* _Harvey P. Dale_, Oct 23 2022 *)
%Y Cf. A000030, A000040, A007089, A077652, A227858.
%K nonn,base,easy
%O 1,1
%A _Jonathan Vos Post_, Nov 06 2013
%E More terms from _Alois P. Heinz_, Nov 07 2013
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