A284201 The successive digits of the sequence are the same digits that have an even rank in the sequence.

1, 10, 11, 0, 2, 12, 100, 3, 20, 13, 21, 110, 30, 4, 31, 200, 5, 14, 32, 22, 15, 16, 120, 6, 300, 7, 40, 33, 17, 210, 50, 8, 51, 18, 41, 34, 23, 24, 25, 19, 52, 106, 9, 102, 60, 26, 43, 70, 80, 27, 44, 90, 53, 63, 61, 37, 42, 71, 101, 500, 28, 35, 81, 91, 38, 54, 111, 36, 45, 29, 39, 204, 62, 55, 112, 92, 56, 201, 103, 64

Offset

1,2

Comments

The sequence is started with a(1) = 1 and always extended with the smallest integer not yet present and not leading to a contradiction.

Links

Jean-Marie Falcoz, Table of n, a(n) for n = 1..3004

Example

The first 15 terms are:
1,10,11,0,2,12,100,3,20,13,21,110,30,4,31
Their successive digits are:
1,1,0,1,1,0,2,1,2,1,0,0,3,2,0,1,3,2,1,1,1,0,3,0,4,3,1
The odd rank digits are here (between parentheses):
(1),1,(0),1,(1),0,(2),1,(2),1,(0),0,(3),2,(0),1,(3),2,(1),1,(1),0,(3),0,(4),3,(1)
Erasing the digits in the parentheses:
( ),1,( ),1,( ),0,( ),1,( ),1,( ),0,( ),2,( ),1,( ),2,( ),1,( ),0,( ),0,( ),3,( )
The surviving digits are:
1,1,0,1,1,0,2,1,2,1,0,0,3...
Those are indeed the digits of the starting sequence.

Crossrefs

Sequence in context: A072804 A079793 A086884 * A324660 A336035 A334676

Adjacent sequences: A284198 A284199 A284200 * A284202 A284203 A284204

Keyword

nonn,base

Author

Eric Angelini and Jean-Marc Falcoz, Mar 22 2017

Extensions

Typo fixed in comments by Rémy Sigrist, Mar 23 2017

Status

approved