This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A380992 #11 Feb 28 2025 15:14:02 %S A380992 2,16,32,128,1024,131072,16777216,137438953472,35184372088832, %T A380992 36028797018963968,1180591620717411303424,151115727451828646838272, %U A380992 162259276829213363391578010288128,174224571863520493293247799005065324265472,1427247692705959881058285969449495136382746624 %N A380992 Powers of two which produce a prime number when their digits are reversed. %C A380992 A057708 is the main entry for this question. - _N. J. A. Sloane_, Feb 28 2025 %F A380992 a(n) = 2^A057708(n). - _Pontus von Brömssen_, Feb 11 2025 %e A380992 The digits of 1024 (2^10) reverse to form the prime number 4201. %t A380992 Select[2^Range[200],PrimeQ[IntegerReverse[#]]&] (* _James C. McMahon_, Feb 28 2025 *) %Y A380992 Cf. A057708. %K A380992 nonn,base %O A380992 1,1 %A A380992 _Paul Duckett_, Feb 11 2025