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 A044873 #10 Sep 11 2021 10:47:07 %S A044873 9,11,13,133,135,140,143,146,148,150,152,154,156,161,164,166,172,175, %T A044873 178,180,182,189,196,198,200,202,206,210,212,214,216,218,220,225,228, %U A044873 230,236,239,241,245,247,2065,2069,2071,2077 %N A044873 Numbers having, in base 2, (sum of even run lengths)=(sum of odd run lengths). %o A044873 (Python) %o A044873 from itertools import groupby %o A044873 def ok(n): %o A044873 rl_sums = [0, 0] %o A044873 for k, g in groupby(bin(n)[2:]): %o A044873 rl = len(list(g)) %o A044873 rl_sums[rl%2] += rl %o A044873 return rl_sums[0] == rl_sums[1] %o A044873 print(list(filter(ok, range(2078)))) # _Michael S. Branicky_, Sep 11 2021 %Y A044873 Cf. A007088. %Y A044873 Cf. A044874, A044875, A044876, A044877, A044878, A044879, A044880. %Y A044873 Cf. A044881, A044882, A044883, A044884, A044885, A044886, A044887. %K A044873 nonn,base %O A044873 1,1 %A A044873 _Clark Kimberling_