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 A263307 #11 Oct 29 2015 23:04:46
%S A263307 1,2,5,10,21,1365,2730
%N A263307 Numbers without consecutive repeated digits in base 2 and in base 3.
%C A263307 Intersection of A000975 and A031941. - _Michel Marcus_, Oct 14 2015
%C A263307 It seems likely that there are no further terms.
%e A263307 10 is 1010 in base 2 and 101 in base 3; no two of the same digit are next to one another and so 10 is a term.
%e A263307 Similarly 21 is 10101 in base 2 and 210 in base 3 so it is also a term.
%o A263307 (PARI) isokd(d) = {dd = vector(#d-1, k, abs(d[k+1]-d[k])); if (#dd, vecmin(dd), 1);}
%o A263307 isok(n) = isokd(binary(n)) && isokd(digits(n, 3)); \\ _Michel Marcus_, Oct 14 2015
%Y A263307 Cf. A000975 (base 2), A031941 (base 3).
%K A263307 nonn,base
%O A263307 1,2
%A A263307 _Robin Powell_, Oct 13 2015