A106747 Replace each odd digit d of n with (d-1)/2 and each even digit d with d/2.

0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 20, 20, 21, 21, 22, 22, 23, 23, 24, 24, 20, 20, 21, 21, 22, 22, 23, 23, 24, 24, 30, 30, 31, 31, 32, 32, 33, 33, 34, 34, 30, 30, 31, 31, 32, 32

Offset: 0

Author

Zak Seidov, May 12 2005

Keywords

• nonn
• base
• look

Comments

Terms are repeated. Differs from A004526 and A021895 starting with a(11)=0, A004526(11)=A021895(11)=5.

Links

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

Crossrefs

Cf. A004526, A021895, A107128, A107130.

Programs

Haskell

a106747 n = if n == 0 then 0 else 10 * (a106747 n') + div d 2
            where (n', d) = divMod n 10
-- Reinhard Zumkeller, Jan 14 2015

Mathematica

a[n_]:=FromDigits[Map[If[Mod[ #, 2]==1, (#-1)/2, #/2]&, IntegerDigits[n]]];Table[a[n], {n, 0, 100}]

Python

def A106747(n): return int(str(n).translate({49:48,50:49,51:49,52:50,53:50,54:51,55:51,56:52,57:52})) # Chai Wah Wu, Apr 07 2022