A107128 Divide the even digits of n by 2!.

0, 1, 1, 3, 2, 5, 3, 7, 4, 9, 10, 11, 11, 13, 12, 15, 13, 17, 14, 19, 10, 11, 11, 13, 12, 15, 13, 17, 14, 19, 30, 31, 31, 33, 32, 35, 33, 37, 34, 39, 20, 21, 21, 23, 22, 25, 23, 27, 24, 29, 50, 51, 51, 53, 52, 55, 53, 57, 54, 59, 30, 31, 31, 33, 32, 35, 33, 37, 34, 39, 70, 71, 71

Offset

0,4

Comments

Differs from A026741 starting with 11-term term: A107128(11)=10, A026741(11)=5.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Mathematica

A107128[n_]:=FromDigits[Map[If[Mod[ #, 2]==0, #/2, # ]&, IntegerDigits[n]]]
Table[FromDigits[If[EvenQ[#], #/2, #]&/@IntegerDigits[n]], {n, 0, 80}] (* Harvey P. Dale, Sep 03 2018 *)

Prog

(Haskell)
a107128 n = if n == 0 then 0 else 10 * (a107128 n') + m * d + (1 - m) * d'
            where (d', m) = divMod d 2
                  (n', d) = divMod n 10
-- Reinhard Zumkeller, Jan 14 2015
(Python)
def A107128(n): return int(str(n).translate({50:49, 52:50, 54:51, 56:52})) # Chai Wah Wu, Apr 08 2022

Crossrefs

Cf. A026741.

Cf. A106747.

Sequence in context: A105658 A083242 A111618 * A086670 A075888 A075889

Adjacent sequences: A107125 A107126 A107127 * A107129 A107130 A107131

Keyword

nonn,base,look

Author

Zak Seidov, May 12 2005

Status

approved