A071649 Sum of odd decimal digits of n.

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, 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, 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

Offset

1,3

Links

Table of n, a(n) for n=1..92.

Formula

a(n) = 0 iff n is in A014263. - Bernard Schott, Mar 17 2023

Maple

A071649 := proc(n)
      local a, d;
      a := 0 ;
      for d in convert(n, base, 10) do
        if type(d, 'odd') then
            a := a+d ;
        end if;
    end do:
    a ;
end proc: # R. J. Mathar, Feb 02 2015

Mathematica

Table[Total[Select[IntegerDigits[n], OddQ[#] &]], {n, 92}] (* Jayanta Basu, May 23 2013 *)

Prog

(PARI) a(n)=my(d=digits(n)); sum(i=1, #d, if(d[i]%2, d[i])) \\ Charles R Greathouse IV, Apr 04 2014
(PARI) A071649(n)=vecsum(select(d->bittest(d, 0), digits(n))) \\ Nearly twice as fast. - M. F. Hasler, Dec 09 2018
(Python)
A071649 = lambda x: sum(d for d in map(int, str(x)) if d&1) # M. F. Hasler, Dec 07 2022

Crossrefs

a(n) = A007953(n) - A071648(n).

Cf. A014263, A071650.

Sequence in context: A167465 A193356 A347347 * A341310 A352505 A210524

Adjacent sequences: A071646 A071647 A071648 * A071650 A071651 A071652

Keyword

nonn,base,easy

Author

Reinhard Zumkeller, May 28 2002

Status

approved