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 A262290 #9 Sep 19 2015 13:10:04 %S A262290 0,3,8,11,17,20,23,29,38,43,49,54,61,70,75,81,84,87,93,102,107,114, %T A262290 119,128,131,136,139,145,148,151,157,167,173,180,187,196,201,206,211, %U A262290 218,225,230,235,244,253,262,267,273,276,279,285,294,299,305,310,317,327,333,340,343,349,358,365,372,381 %N A262290 a(0)=0; thereafter, add the smallest nonzero binary number, not a power of 2, that is not a substring of the binary expansion of a(n). %F A262290 a(n+1) = a(n) + A262289(a(n)). %Y A262290 Cf. A260273, A262289. %Y A262290 Identical to A261416 except for first two terms. %K A262290 nonn,base %O A262290 0,2 %A A262290 _N. J. A. Sloane_, Sep 19 2015