A178788 Characteristic function of numbers having distinct digits in their decimal representation.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1

Offset

0,1

Comments

a(A010784(n)) = 1; a(A109303(n)) = 0;

first differences of A178787.

a(n) <= A196368(n).

a(n) = 0 for n > 9*9!. - Hieronymus Fischer, Feb 02 2013

Links

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

Eric Weisstein's World of Mathematics, Digit

Index entries for characteristic functions

Michael De Vlieger, Plot a(n) at (x,y) = (n mod 1000, -floor(n/1000)), n = 1..10^6, where black represents a(n) = 1 and white represents a(n) = 0.

Formula

a(n) = 0^(A055642(n)-A043537(n)).

Mathematica

lst = {}; Do[If[Select[Tally[IntegerDigits[n]][[All, 2]], # > 1 &] == {}, AppendTo[lst, 1], AppendTo[lst, 0]], {n, 0, 104}]; lst (* Arkadiusz Wesolowski, May 10 2012 *)

Prog

(Haskell)
import Data.List (nub)
a178788 n = fromEnum $ nub (show n) == show n
-- Reinhard Zumkeller, Sep 25 2011

Crossrefs

Sequence in context: A294935 A242902 A196368 * A131217 A105567 A114213

Adjacent sequences: A178785 A178786 A178787 * A178789 A178790 A178791

Keyword

base,nonn,changed

Author

Reinhard Zumkeller, Jun 30 2010

Status

approved