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A033010 Numbers each of whose runs of digits in base 12 has length 2.

%I A033010 #20 Apr 28 2021 02:43:28
%S A033010 13,26,39,52,65,78,91,104,117,130,143,1872,1898,1911,1924,1937,1950,
%T A033010 1963,1976,1989,2002,2015,3744,3757,3783,3796,3809,3822,3835,3848,
%U A033010 3861,3874,3887,5616,5629,5642,5668,5681,5694,5707,5720,5733,5746,5759,7488,7501
%N A033010 Numbers each of whose runs of digits in base 12 has length 2.
%C A033010 See A043291 and A033001 through A033014 for the analog in other bases, A033015 - A033029 for the variants with run lengths >= 2. - _M. F. Hasler_, Feb 02 2014
%C A033010 Numbers without repeating adjacent digits for which all digits are divisible by 13, in base 144. Consequently there are 11^n n-digit members of this sequence (base 144) and so (11^(n+1)-1)/10 members of this sequence below 144^n. - _Charles R Greathouse IV_, Feb 02 2014
%H A033010 Vincenzo Librandi, <a href="/A033010/b033010.txt">Table of n, a(n) for n = 1..1400</a>
%F A033010 a(n) = 13*A043316(n) (= 13*n for n < 12). - _M. F. Hasler_, Feb 02 2014
%t A033010 Select[Range[10000], Union[Length/@Split[IntegerDigits[#, 12]]]=={2}&] (* _Vincenzo Librandi_, Feb 05 2014 *)
%o A033010 (Python)
%o A033010 from sympy.ntheory import digits
%o A033010 from itertools import groupby
%o A033010 def ok(n):
%o A033010   return all(len(list(g))==2 for k, g in groupby(digits(n, 12)[1:]))
%o A033010 print(list(filter(ok, range(1, 7502)))) # _Michael S. Branicky_, Apr 27 2021
%K A033010 nonn,base,easy
%O A033010 1,1
%A A033010 _Clark Kimberling_