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A317029 Invertible primes p such that k*p - 1 and k*p + 1 is a twin prime pair; for k = 12.

%I A317029 #9 Nov 14 2018 12:11:11
%S A317029 19,601,1601,16661,16981,19609,60689,66809,69001,69011,100169,119191,
%T A317029 189901,196919,616961,1061689,1088089,1091119,1106069,1196089,1198069,
%U A317029 1611601,1666019,1688969,1800119,1861889,1891619,1891661,1910669,1996681,6060091,6160601,6196909
%N A317029 Invertible primes p such that k*p - 1 and k*p + 1 is a twin prime pair; for k = 12.
%C A317029 Intersection of A048890 (invertible primes) and A138242.
%C A317029 k = 12 is the smallest integer to produce such sequence.
%e A317029 a(2) = 601 is an invertible prime; 12*601 - 1 = 7211; 12*601 + 1 = 7213; 7211 and 7213 form a twin prime pair.
%e A317029 a(4) = 16661 is an invertible prime; 12*16661 - 1 = 199931; 12*16661 + 1 = 199933; 199931 and 199933 form a twin prime pair.
%t A317029 k = 12; Select[lst = {};
%t A317029 fQ[n_] := Block[{allset = {0, 1, 6, 8, 9}, id = IntegerDigits@n}, rid = Reverse[id /. {6 -> 9, 9 -> 6}];Union@Join[id, allset] == allset && PrimeQ@FromDigits@rid && rid != id];Do[If[PrimeQ@n && fQ@n, AppendTo[lst, n]], {n, 12000000}]; lst,
%t A317029 PrimeQ[k# + 1] && PrimeQ[k# - 1] &]
%Y A317029 Cf. A048890, A001359, A006512, A124519, A138242.
%K A317029 nonn,base
%O A317029 1,1
%A A317029 _K. D. Bajpai_, Jul 19 2018