A033007 Every run of digits of n in base 9 has length 2.
10, 20, 30, 40, 50, 60, 70, 80, 810, 830, 840, 850, 860, 870, 880, 890, 1620, 1630, 1650, 1660, 1670, 1680, 1690, 1700, 2430, 2440, 2450, 2470, 2480, 2490, 2500, 2510, 3240, 3250, 3260, 3270, 3290, 3300, 3310, 3320, 4050
Offset: 1
Links
- Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Programs
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Mathematica
Select[Range[10000], Union[Length/@Split[IntegerDigits[#, 9]]]=={2}&] (* Vincenzo Librandi, Feb 05 2014 *)
Formula
a(n) = 10*A043313(n) (= 10*n for n<9). - M. F. Hasler, Feb 02 2014
Comments