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A306301 Numbers k such that k^2 reversed is a prime and k^2+(k^2 reversed) is a prime.

%I A306301 #51 Apr 10 2019 02:55:11
%S A306301 14,136,190,266,280,1036,1060,1306,1406,1898,1934,2660,2686,2746,2776,
%T A306301 3112,10040,10250,10546,10550,10630,10880,11090,11156,11204,11276,
%U A306301 11354,11386,11474,11740,11804,11914,12064,12136,12194,12250,12410,12524,12626,12710,12770,12794,12916,13060
%N A306301 Numbers k such that k^2 reversed is a prime and k^2+(k^2 reversed) is a prime.
%C A306301 All terms are even and not divisible by 3. - _Robert Israel_, Apr 09 2019
%H A306301 Robert Israel, <a href="/A306301/b306301.txt">Table of n, a(n) for n = 1..10000</a>
%e A306301 14 is a term because 691 (the reverse of 14^2=196) and 196+691=887 are two prime numbers.
%p A306301 revdigs:= proc(n) local L,i;
%p A306301   L:= convert(n,base,10);
%p A306301   add(L[-i]*10^(i-1),i=1..nops(L))
%p A306301 end proc:
%p A306301 filter:= proc(k) local v; v:= revdigs(k^2); isprime(v) and isprime(v+k^2) end proc:
%p A306301 select(filter, [seq(seq(6*i+j,j=[2,4]),i=0..10000)]); # _Robert Israel_, Apr 09 2019
%t A306301 Select[Range[50000], PrimeQ[IntegerReverse[#^2]] && PrimeQ[#^2 + IntegerReverse[#^2]] &]
%o A306301 (PARI) isok(k) = my(kk=fromdigits(Vecrev(digits(k^2)))); isprime(kk) && isprime(k^2+kk); \\ _Michel Marcus_, Apr 01 2019
%Y A306301 Cf. A007488, A059007, A307046.
%K A306301 nonn,base
%O A306301 1,1
%A A306301 _Robert Price_, Mar 31 2019