

A163501


Lexicographically earliest sequence of distinct positive integers such that a(n) shares no digit with a(a(n)) for all n.


4



2, 1, 4, 3, 6, 5, 8, 7, 10, 9, 12, 30, 14, 20, 16, 22, 18, 23, 21, 31, 33, 34, 40, 25, 36, 27, 35, 29, 37, 41, 42, 38, 44, 50, 46, 45, 48, 47, 43, 51, 52, 53, 55, 56, 60, 57, 58, 59, 54, 61, 62, 63, 64, 66, 67, 70, 68, 69, 71, 72, 73, 74, 75, 77, 76, 78, 80, 79, 81, 82, 83, 84
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OFFSET

1,1


COMMENTS

This is an example of a sequence whose initial behavior is quite different from its limiting behavior. It starts out looking as though most numbers will appear in the sequence, but in fact it has density 0. It can't include any number that has all nine nonzero digits, and those have density 1.  Franklin T. AdamsWatters, Apr 03 2009


LINKS

David W. Wilson, Table of n, a(n) for n = 1..10000


EXAMPLE

a(1)=2 shares no digit with a(a(1))=a(2)=1;
a(2)=1 shares no digit with a(a(2))=a(1)=2; ...
a(11)=12 shares no digit with a(a(11))=a(12)=30, etc.
In building the sequence, always use the smallest available positive integer not yet present in the sequence.


CROSSREFS

Cf. A152200 (complement), A152208 (a variant), A152209.
Sequence in context: A014681 A103889 A137805 * A306229 A096779 A243500
Adjacent sequences: A163498 A163499 A163500 * A163502 A163503 A163504


KEYWORD

base,nonn


AUTHOR

Eric Angelini, Jul 29 2009


EXTENSIONS

Terms discussed, checked and computed by Paolo P. Lava, Jacques Tramu and Farideh Firoozbakht
Edited by Max Alekseyev, Feb 11 2012


STATUS

approved



