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 A264647 #14 Sep 22 2021 07:36:59
%S A264647 1,2,6,4,10,8,79,199,9,108,11,29,17,15,40,80,20,59,306,22,169,38,27,
%T A264647 82,287,41,49,209,47,135,31,36,127,112,123,162,46,89,63,54,581,43,56,
%U A264647 770,67,48,134,52,142,69,58,101,382,466,75,64,273,95,117,126,72
%N A264647 Smallest number m such that A263856(m) = n.
%C A264647 a(6949) > 22700000 if it exists. - _Chai Wah Wu_, Feb 01 2016
%H A264647 Reinhard Zumkeller and Chai Wah Wu, <a href="/A264647/b264647.txt">Table of n, a(n) for n = 1..6948</a> n = 1..391 from Reinhard Zumkeller
%F A264647 A263856(a(n)) = n and A263856(m) != n for m < a(n).
%t A264647 f[p_] := f[p] = StringJoin @@ ToString /@ Reverse[IntegerDigits[p, 2]];
%t A264647 S[n_] := S[n] = SortBy[Prime[Range[n]], f];
%t A264647 A263856[n_] := A263856[n] = FirstPosition[S[n], Prime[n]][[1]];
%t A264647 a[n_] := a[n] = For[m = 1, True, m++, If[A263856[m] == n, Return[m]]];
%t A264647 Table[Print[n, " ", a[n]]; a[n], {n, 1, 391}] (* _Jean-François Alcover_, Sep 22 2021 *)
%o A264647 (Haskell)
%o A264647 import Data.List (elemIndex); import Data.Maybe (fromJust)
%o A264647 a264647 = (+ 1) . fromJust . (`elemIndex` a263856_list)
%Y A264647 Cf. A263856.
%K A264647 nonn
%O A264647 1,2
%A A264647 _Reinhard Zumkeller_, Nov 19 2015