login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A137564 The number formed by removing from n all duplicate digits except the leftmost copy of each. 4
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 2, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 3, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 4, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 5, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 6, 67, 68, 69, 70, 71, 72, 73, 74 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(n)=n iff n is a term of A010784. a(n)<n iff n is a term of A109303.

LINKS

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

EXAMPLE

a(100)=10 as a (second) 0 digit is dropped. a(100) is the first term differing from A106612's terms: A106612(100)=100. a(1211323171)=1237.

MATHEMATICA

Table[FromDigits@ DeleteDuplicates@ IntegerDigits@ n, {n, 74}] (* Michael De Vlieger, Jun 01 2016 *)

PROG

(Haskell)

a137564 = f (-1) where

   f _ 0 = 0

   f r x = if d == r then f r x' else 10 * f d x' + d

           where (x', d) = divMod x 10

-- Reinhard Zumkeller, Jan 28 2015

CROSSREFS

Cf. A106612, A010784, A109303.

Sequence in context: A180409 A320485 A321802 * A106612 A056960 A227362

Adjacent sequences:  A137561 A137562 A137563 * A137565 A137566 A137567

KEYWORD

base,easy,nonn

AUTHOR

Rick L. Shepherd, Jan 25 2008

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 15 18:59 EST 2019. Contains 329149 sequences. (Running on oeis4.)