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%I #25 Mar 10 2023 13:32:59
%S 17,34,51,68,85,102,119,136,153,170,187,204,221,238,255,4352,4386,
%T 4403,4420,4437,4454,4471,4488,4505,4522,4539,4556,4573,4590,4607,
%U 8704,8721,8755,8772,8789,8806,8823,8840,8857,8874
%N Every run of digits of n in base 16 has length 2.
%H Vincenzo Librandi, <a href="/A033014/b033014.txt">Table of n, a(n) for n = 1..2000</a>
%F a(n) = 17*A043320(n) (= 17n for n<16, cf Example). - _M. F. Hasler_, Feb 02 2014
%e In base 16, a(1)=17 is written 11; the subsequent 14 values are the multiples of 17, corresponding to 22, 33, 44, ..., FF).
%e This is followed by a(16) = 4352 = 1100[16], then (still in base 16): 1122, 1133,..., 11FF, 2200, 2211, 2233, etc...
%t Select[Range[9000],Union[Length/@Split[IntegerDigits[#,16]]]=={2}&] (* _Harvey P. Dale_, Jan 19 2013 *)
%o (Python)
%o from itertools import count, islice, groupby
%o def A033014_gen(startvalue=1): # generator of terms >= startvalue
%o return filter(lambda n:set(len(list(g)) for k, g in groupby(hex(n)[2:]))=={2},count(max(startvalue,1)))
%o A033014_list = list(islice(A033014_gen(),20)) # _Chai Wah Wu_, Mar 10 2023
%Y See A033001 for further cross-references.
%K nonn,base
%O 1,1
%A _Clark Kimberling_
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