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 A333778 #5 Apr 07 2020 08:49:51
%S A333778 0,1,2,3,4,7,8,10,15,16,29,31,32,36,42,57,63,64,86,113,127,128,136,
%T A333778 170,225,251,255,256,292,338,449,477,499,511,512,528,588,674,682,897,
%U A333778 949,995,1023,1024,1172,1346,1390,1793,1849,1893,1987,2039,2047,2048,2080
%N A333778 Fixed points of A333776.
%C A333778 This sequence contains A000079, A000225.
%o A333778 (PARI) is(n, base=2) = { my (d=digits(n, base), t=[]); forstep (k=#d, 1, -1, if (d[k], t=Vecrev(t);); t=concat(d[k], t)); n==fromdigits(t, base) }
%Y A333778 Cf. A000079, A000225, A333776, A333777.
%K A333778 nonn,base
%O A333778 1,3
%A A333778 _Rémy Sigrist_, Apr 05 2020