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%I #19 Feb 02 2021 13:35:10
%S 809,66089,68099,86069,88069,89069,99089,6680689,6680699,6680969,
%T 6690689,6690899,6690989,6860869,6860989,6860999,6890699,6890969,
%U 6960869,6980669,6980899,6980969,6990889,8660689,8660699,8660969
%N Cyclops primes with circular digits {0,6,8,9}.
%C The sequence is probably infinite.
%C The sequence A134809 restricted to cases with digits 6, 8 or 9 (see A001743) at the off-center positions.
%C Primes in A274765. - _Omar E. Pol_, Jul 06 2016
%C Each term is equal to 9 mod 10. - _Harvey P. Dale_, Feb 02 2021
%H Kenny Lau, <a href="/A160561/b160561.txt">Table of n, a(n) for n = 1..20000</a>
%t Select[Prime@ Range[10^6], And[OddQ@ Length@ #, Times @@ Boole@ Map[MemberQ[{0, 6, 8, 9}, #] &, Union@ #] == 1, Part[#, Ceiling[Length[#]/2]] == 0, Count[#, 0] == 1] &@ IntegerDigits@ # &] (* _Michael De Vlieger_, Jul 05 2016 *)
%t Table[Select[FromDigits/@(Flatten[Join[{Take[#,Length[#]/2],0,Take[#,-Length[#]/2]}]]&/@Tuples[{6,8,9},n]),PrimeQ],{n,2,6,2}]//Flatten (* _Harvey P. Dale_, Feb 02 2021 *)
%Y Intersection of A000040 (primes), A001743 (numbers with circular digits) and A134808 (cyclops numbers).
%Y Also intersection of A043580 (primes with circular digits) and A134809 (cyclops primes).
%Y Cf. A134808, A134809, A153807, A156200, A274765.
%K nonn,base
%O 1,1
%A _Ki Punches_, May 19 2009
%E Edited and corrected by _Ray Chandler_ and _R. J. Mathar_, May 20 2009
%E Definition simplified by _Omar E. Pol_, Jun 05 2009
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