OFFSET
1,1
COMMENTS
The relevant exponents are collected in A057708.
a(23), reverse(2^3489), has 1023 decimal digits. - Michael De Vlieger, Dec 03 2015
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..22
FORMULA
a(n) = reverse(2^A057708(n)).
EXAMPLE
Reverse 128, obtain 821, a prime.
MATHEMATICA
Select[FromDigits@ Reverse@ IntegerDigits[2^#] & /@ Range@ 3200, PrimeQ] (* Michael De Vlieger, Dec 03 2015 *)
PROG
(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
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Labos Elemer, Jan 28 2005
STATUS
approved