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%I #28 Mar 17 2023 06:41:51
%S 1,0,3,0,5,0,7,0,9,1,2,1,4,1,6,1,8,1,10,0,1,0,3,0,5,0,7,0,9,3,4,3,6,3,
%T 8,3,10,3,12,0,1,0,3,0,5,0,7,0,9,5,6,5,8,5,10,5,12,5,14,0,1,0,3,0,5,0,
%U 7,0,9,7,8,7,10,7,12,7,14,7,16,0,1,0,3,0,5,0,7,0,9,9,10,9
%N Sum of odd decimal digits of n.
%F a(n) = 0 iff n is in A014263. - _Bernard Schott_, Mar 17 2023
%p A071649 := proc(n)
%p local a,d;
%p a := 0 ;
%p for d in convert(n,base,10) do
%p if type(d,'odd') then
%p a := a+d ;
%p end if;
%p end do:
%p a ;
%p end proc: # _R. J. Mathar_, Feb 02 2015
%t Table[Total[Select[IntegerDigits[n], OddQ[#] &]],{n,92}] (* _Jayanta Basu_, May 23 2013 *)
%o (PARI) a(n)=my(d=digits(n)); sum(i=1,#d,if(d[i]%2,d[i])) \\ _Charles R Greathouse IV_, Apr 04 2014
%o (PARI) A071649(n)=vecsum(select(d->bittest(d,0), digits(n))) \\ Nearly twice as fast. - _M. F. Hasler_, Dec 09 2018
%o (Python)
%o A071649 = lambda x: sum(d for d in map(int, str(x)) if d&1) # _M. F. Hasler_, Dec 07 2022
%Y a(n) = A007953(n) - A071648(n).
%Y Cf. A014263, A071650.
%K nonn,base,easy
%O 1,3
%A _Reinhard Zumkeller_, May 28 2002
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