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A033014
Every run of digits of n in base 16 has length 2.
28
17, 34, 51, 68, 85, 102, 119, 136, 153, 170, 187, 204, 221, 238, 255, 4352, 4386, 4403, 4420, 4437, 4454, 4471, 4488, 4505, 4522, 4539, 4556, 4573, 4590, 4607, 8704, 8721, 8755, 8772, 8789, 8806, 8823, 8840, 8857, 8874
OFFSET
1,1
LINKS
FORMULA
a(n) = 17*A043320(n) (= 17n for n<16, cf Example). - M. F. Hasler, Feb 02 2014
EXAMPLE
In base 16, a(1)=17 is written 11; the subsequent 14 values are the multiples of 17, corresponding to 22, 33, 44, ..., FF.
This is followed by a(16) = 4352 = 1100[16], then (still in base 16): 1122, 1133,..., 11FF, 2200, 2211, 2233, etc...
MATHEMATICA
Select[Range[9000], Union[Length/@Split[IntegerDigits[#, 16]]]=={2}&] (* Harvey P. Dale, Jan 19 2013 *)
PROG
(Python)
from itertools import count, islice, groupby
def A033014_gen(startvalue=1): # generator of terms >= startvalue
return filter(lambda n:set(len(list(g)) for k, g in groupby(hex(n)[2:]))=={2}, count(max(startvalue, 1)))
A033014_list = list(islice(A033014_gen(), 20)) # Chai Wah Wu, Mar 10 2023
CROSSREFS
See A033001 for further cross-references.
Sequence in context: A008599 A033029 A044842 * A070814 A188290 A268287
KEYWORD
nonn,base
STATUS
approved