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%I #26 Sep 19 2021 12:18:50
%S 9,19,29,39,49,59,69,79,89,90,91,92,93,94,95,96,97,98,109,119,129,139,
%T 149,159,169,179,189,190,191,192,193,194,195,196,197,198,209,219,229,
%U 239,249,259,269,279,289,290,291,292,293,294,295,296,297,298,309,319
%N Numbers having one 9 in base 10.
%H Enrique Pérez Herrero, <a href="/A043525/b043525.txt">Table of n, a(n) for n = 1..2000</a>
%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.
%F Sum_{n>=1} 1/a(n) = A140502. - _Amiram Eldar_, Nov 14 2020
%t Select[Range[300],DigitCount[#,10,9]==1&] (* _Harvey P. Dale_, Jan 19 2013 *)
%o (Python)
%o def ok(n): return str(n).count('9') == 1
%o print(list(filter(ok, range(320)))) # _Michael S. Branicky_, Sep 19 2021
%Y Cf. A043489, A043493, A043497, A043501, A043505, A043509, A043513, A043517, A043521.
%Y Cf. A011539, A140502.
%Y Subsequence of A011539.
%K nonn,base
%O 1,1
%A _Clark Kimberling_
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