A210524 a(n) = n - sum of even digits of n.

0, 1, 0, 3, 0, 5, 0, 7, 0, 9, 10, 11, 10, 13, 10, 15, 10, 17, 10, 19, 18, 19, 18, 21, 18, 23, 18, 25, 18, 27, 30, 31, 30, 33, 30, 35, 30, 37, 30, 39, 36, 37, 36, 39, 36, 41, 36, 43, 36, 45, 50, 51, 50, 53, 50, 55, 50, 57, 50, 59, 54, 55, 54, 57, 54, 59, 54, 61

Offset

0,4

Comments

In even positions there are odd terms.

The difference between n and even digits of n and n has odd and even digits gives even terms finishing with 0.

Links

Table of n, a(n) for n=0..67.

Formula

a(n) ~ n. a(n) = n mod 2. - Charles R Greathouse IV, Jan 28 2013

Example

a(14) = 14 - 4 = 10.
a(28) = 28 - 2 - 8 = 18.

Mathematica

Table[n-Total[Select[IntegerDigits[n], EvenQ]], {n, 0, 90}] (* Harvey P. Dale, May 20 2017 *)

Prog

(PARI) a(n) = {digs = digits(n, 10); return (n - sum(i=1, #digs, digs[i]*(1 - (digs[i] % 2)))); } \\ Michel Marcus, Jul 15 2013

Crossrefs

Cf. A066568.

Sequence in context: A071649 A341310 A352505 * A325961 A049283 A141162

Adjacent sequences: A210521 A210522 A210523 * A210525 A210526 A210527

Keyword

nonn,base,easy

Author

Marco Piazzalunga, Jan 27 2013

Status

approved