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%I #9 Jan 16 2022 13:35:48
%S 3,5,7,11,13,17,31,71,101,151,181,191,313,1031,1033,1231,1279,1301,
%T 1321,1429,1453,1933,3301,3391,3541,3583,3853,7349,7457,7547,7589,
%U 9241,9437,9679,9721,9769,9857,10007,10067,10273,10301,10429,10457,10501,10711,10859,11057,11701,11717,11777,11833
%N Twin primes whose base-10 digit reversals are also twin primes.
%C Intersection of A001097 and A004086(A001097).
%H Robert Israel, <a href="/A333207/b333207.txt">Table of n, a(n) for n = 1..10000</a>
%e a(5) = 13 is in the sequence because both 13 and its reversal 31 are twin primes.
%p revdigs:= proc(n) local L,k;
%p L:= convert(n,base,10);
%p add(L[-k]*10^(k-1),k=1..nops(L))
%p end proc:
%p Pr:= select(isprime, {seq(i,i=3..10^5,2)}):
%p TL:= Pr intersect map(`-`,Pr,2):
%p T:= TL union map(`+`,TL,2):
%p sort(convert(select(t-> member(revdigs(t),T), T),list));
%t tpQ[p_]:=PrimeQ[IntegerReverse[p]]&&AnyTrue[p+{2,-2},PrimeQ]; Select[ Prime[ Range[1500]],tpQ[#]&&tpQ[IntegerReverse[#]]&] (* _Harvey P. Dale_, Jan 16 2022 *)
%Y Cf. A004086, A001097. Includes A083840.
%K nonn,base
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Mar 11 2020
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