%I #47 Nov 11 2022 11:50:40
%S 1,3,5,7,9,10,12,14,16,18,21,23,25,27,29,30,32,34,36,38,41,43,45,47,
%T 49,50,52,54,56,58,61,63,65,67,69,70,72,74,76,78,81,83,85,87,89,90,92,
%U 94,96,98,100,102,104,106,108,111,113,115,117,119,120,122,124,126,128,131
%N Numbers whose sum of digits is odd.
%C Union of A179083 and A179085; A179081(a(n)) = 1. - _Reinhard Zumkeller_, Jun 28 2010
%C Equivalently, integers with an odd number of odd digits. - _Bernard Schott_, Nov 06 2022
%H Reinhard Zumkeller, <a href="/A054684/b054684.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.
%H <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%F a(n) = n * 2 - 1 for the first 5 numbers; a(n) = n * 2 for the second 5 numbers.
%F From _Robert Israel_, Jun 27 2017: (Start)
%F a(n) = 2*n-2 if floor((n-1)/5) is in the sequence, 2*n-1 if not.
%F G.f. g(x) satisfies g(x) = (1-x)*(1+x+x^2+x^3+x^4)^2*g(x^10)/x^9 + x^2*(2+x^4+3*x^5-x^9+3*x^10)/((1-x)*(1+x^5))^2.
%F (End)
%e 1, 3, 5, 7, 9, 10(1), 12(3), 14(5), 16(7), 18(9), 21(3) and so on.
%p [seq(`if`(convert(convert(2*n-1,base,10),`+`)::odd, 2*n-1, 2*n-2), n=1..501)];
%t Select[Range[200],OddQ[Total[IntegerDigits[#]]]&] (* _Harvey P. Dale_, Nov 27 2021 *)
%o (PARI) is(n)=my(d=digits(n));sum(i=1,#d,d[i])%2 \\ _Charles R Greathouse IV_, Aug 09 2013
%o (PARI) isok(m) = sumdigits(m) % 2; \\ _Michel Marcus_, Nov 06 2022
%o (PARI) a(n) = n=2*(n-1); n + !(sumdigits(n)%2); \\ _Kevin Ryde_, Nov 07 2022
%o (Python)
%o def ok(n): return sum(map(int, str(n)))&1
%o print([k for k in range(132) if ok(k)]) # _Michael S. Branicky_, Nov 06 2022
%Y Cf. A054683, A137233 (number of n-digits terms).
%Y Cf. A356929 (even number of even digits).
%Y A294601 (exactly one odd decimal digit) is a subsequence.
%K nonn,easy,base
%O 1,2
%A _Odimar Fabeny_, Apr 19 2000
%E More terms from _James A. Sellers_, Apr 19 2000