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%I #20 May 04 2019 09:26:49
%S 2,61,23,821,4201,270131,61277761,274359834731,23888027348153,
%T 86936981079782063,4243031147170261950811,272838646828154727511151,
%U 821882010875193363312928672952261,274562423560500997742392394025368175422471,4266472836315949449695828501889595072967427241
%N Primes obtained if 2^j for some suitable j is written backward.
%C The relevant exponents are collected in A057708.
%C a(23), reverse(2^3489), has 1023 decimal digits. - _Michael De Vlieger_, Dec 03 2015
%H Michael De Vlieger, <a href="/A101896/b101896.txt">Table of n, a(n) for n = 1..22</a>
%F a(n) = reverse(2^A057708(n)).
%e Reverse 128, obtain 821, a prime.
%t Select[FromDigits@ Reverse@ IntegerDigits[2^#] & /@ Range@ 3200, PrimeQ] (* _Michael De Vlieger_, Dec 03 2015 *)
%o (GAP) a:=Filtered(List(List([1..300],j->Reversed(ListOfDigits(2^j))),k->Sum([1..Size(k)],i->k[i]*10^(Size(k)-i))),IsPrime);; Print(a); # _Muniru A Asiru_, Dec 25 2018
%Y Cf. A057708.
%K base,nonn
%O 1,1
%A _Labos Elemer_, Jan 28 2005
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