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A107130 Replace each odd digit d of n with (d-1)/2. 2
0, 0, 2, 1, 4, 2, 6, 3, 8, 4, 0, 0, 2, 1, 4, 2, 6, 3, 8, 4, 20, 20, 22, 21, 24, 22, 26, 23, 28, 24, 10, 10, 12, 11, 14, 12, 16, 13, 18, 14, 40, 40, 42, 41, 44, 42, 46, 43, 48, 44, 20, 20, 22, 21, 24, 22, 26, 23, 28, 24, 60, 60, 62, 61, 64, 62, 66, 63, 68, 64, 30, 30, 32, 31, 34, 32 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
Differs from A065423 starting with a(10) = 0, A065423(10) = 10.
LINKS
MATHEMATICA
a[n_]:=FromDigits[Map[If[Mod[ #, 2]==1, (#-1)/2, # ]&, IntegerDigits[n]]]; Table[a[n], {n, 0, 100}]
PROG
(Python)
def A107130(n): return int(str(n).translate({49:48, 51:49, 53:50, 55:51, 57:52})) # Chai Wah Wu, Apr 07 2022
(PARI) a(n)=fromdigits(apply(d->if(d%2, d\2, d), digits(n))) \\ Charles R Greathouse IV, Apr 07 2022
CROSSREFS
Cf. A065423.
Sequence in context: A349442 A130742 A130107 * A194747 A065423 A239242
KEYWORD
nonn,base,easy
AUTHOR
Zak Seidov, May 12 2005
EXTENSIONS
Edited by Charles R Greathouse IV, Aug 03 2010
STATUS
approved

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Last modified May 13 19:11 EDT 2024. Contains 372522 sequences. (Running on oeis4.)