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%I #16 Dec 16 2014 15:06:49
%S 157,709,1283,1321,3469,3929,9643,15101,15241,15383,17443,18439,19237,
%T 30643,35911,38393,39799,71711,73849,78901,92381,92503,93971,94219,
%U 98317,105929,106427,106721,111821,112481,123923,128879,130693,146989,149893,152407,165449
%N Emirps whose binary conversion remains emirp when read in decimal.
%H K. D. Bajpai, <a href="/A226972/b226972.txt">Table of n, a(n) for n = 1..1691</a> (numbers < 4*10^7)
%e For n=1 the a(1)=157 and its reversal 751, both are different and primes. The binary conversion of 157 is 10011101 and its reversal 10111001, both are different and primes.
%p with(numtheory):with(StringTools):
%p # ==== DECI EMIRP ===== BINARY EMIRP ===
%p PRS:= proc(x,y)
%p local i,a,a1,a2,b,c,d,e,f,g,h,m,count;
%p count:=1;
%p for i from x to y do;
%p a:=ithprime(i);
%p a1:=parse(Reverse(convert((a),string)));
%p a2:=isprime(a1);
%p b:=convert(a,binary);
%p c:=isprime(b);
%p d:=parse(Reverse(convert((b),string)));
%p e:=isprime(d);
%p g:=length(a);
%p h:= length(d);
%p if a2 and c and e and a<>a1 and d<>b then lprint(count,a) ;count:=count+1;fi ; od;
%p lprint("Finished " ):
%p end:
%p PRS(1,100000);
%t Select[Prime@Range@20000, PrimeQ[r = FromDigits@Reverse@IntegerDigits[#]] && r != # && PrimeQ[b = FromDigits[d = IntegerDigits[#, 2]]] && b != (br = FromDigits@ Reverse@d) && PrimeQ[br] &] (* _Giovanni Resta_, Jun 25 2013 *)
%Y Cf. A006567 (Emirps, primes whose reversal is a different prime).
%K nonn,base
%O 1,1
%A _K. D. Bajpai_, Jun 24 2013
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