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A098160 Numbers n with property that when writing down all the natural numbers from 0 to n one uses the same number of even and odd digits. 0
1, 3, 5, 7, 9, 10, 28, 29, 30, 48, 49, 50, 68, 69, 70, 88, 89, 90 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The sequence seems to stop at 90.

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

[0,1,2,3,4,5,6,7,8,9,10] uses 6 even digits and 6 odd digits.

MATHEMATICA

f[n_] := Block[{id = Mod[ Flatten[ Table[ IntegerDigits[i], {i, 0, n}]], 2]}, Length[id] - 2Plus @@ id]; Select[ Range[ 100], f[ # ] == 0 &] (* Robert G. Wilson v, Nov 03 2004 *)

sneoQ[n_]:=Module[{d=Flatten[IntegerDigits/@Range[0, n]]}, 2*Count[ d, _?OddQ] == Length[d]]; Select[Range[100], sneoQ] (* Harvey P. Dale, Jul 31 2017 *)

CROSSREFS

Sequence in context: A066929 A173909 A165249 * A103701 A206544 A122799

Adjacent sequences:  A098157 A098158 A098159 * A098161 A098162 A098163

KEYWORD

base,easy,nonn,fini,full

AUTHOR

Eric Angelini, Oct 25 2004

STATUS

approved

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Last modified August 1 09:25 EDT 2021. Contains 346385 sequences. (Running on oeis4.)