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A304440
Add to n the sum of its even digits minus the sum of its odd digits.
4
0, 0, 4, 0, 8, 0, 12, 0, 16, 0, 9, 9, 13, 9, 17, 9, 21, 9, 25, 9, 22, 22, 26, 22, 30, 22, 34, 22, 38, 22, 27, 27, 31, 27, 35, 27, 39, 27, 43, 27, 44, 44, 48, 44, 52, 44, 56, 44, 60, 44, 45, 45, 49, 45, 53, 45, 57, 45, 61, 45, 66, 66, 70, 66, 74, 66, 78, 66, 82, 66, 63
OFFSET
0,3
COMMENTS
A036301 lists fixed points of this map, the first nonzero one being 112. It is also a subsequence of A124177 (and A124176) which lists numbers which are in a cyclic orbit under iterations of this map.
FORMULA
a(n) = n - A071650(n).
MATHEMATICA
nseo[n_]:=Module[{idn=IntegerDigits[n]}, n+Total[Select[idn, EvenQ]]-Total[Select[idn, OddQ]]]; Array[nseo, 80, 0] (* Harvey P. Dale, Dec 26 2023 *)
PROG
(PARI) A304440(n)=n+vecsum(apply(t->t*(-1)^t, digits(n)))
CROSSREFS
Cf. A304439 (variant: + even - odd digits), A071650 (odd - even digits), A071648, A071649, A036301 (fixed points), A124177, A124176.
Sequence in context: A076261 A070802 A114401 * A073467 A288096 A021249
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, May 18 2018
STATUS
approved