cp's OEIS Frontend

A044881 Numbers having, in base 10, (sum of even run lengths)=(sum of odd run lengths).

%I A044881 #11 Sep 11 2021 10:46:57
%S A044881 1001,1002,1003,1004,1005,1006,1007,1008,1009,1011,1022,1033,1044,
%T A044881 1055,1066,1077,1088,1099,1101,1102,1103,1104,1105,1106,1107,1108,
%U A044881 1109,1120,1121,1123,1124,1125,1126,1127,1128,1129
%N A044881 Numbers having, in base 10, (sum of even run lengths)=(sum of odd run lengths).
%o A044881 (Python)
%o A044881 from itertools import groupby
%o A044881 def ok(n):
%o A044881     rl_sums = [0, 0]
%o A044881     for k, g in groupby(str(n)):
%o A044881         rl = len(list(g))
%o A044881         rl_sums[rl%2] += rl
%o A044881     return rl_sums[0] == rl_sums[1]
%o A044881 print(list(filter(ok, range(1130)))) # _Michael S. Branicky_, Sep 11 2021
%Y A044881 Cf. A000027.
%Y A044881 Cf. A044873, A044874, A044875, A044876, A044877, A044878, A044879.
%Y A044881 Cf. A044880, A044882, A044883, A044884, A044885, A044886, A044887.
%K A044881 nonn,base
%O A044881 1,1
%A A044881 _Clark Kimberling_