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A210524
a(n) = n - sum of even digits of n.
0
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.
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
KEYWORD
nonn,base,easy
AUTHOR
Marco Piazzalunga, Jan 27 2013
STATUS
approved