

A276104


Lexicographically first sequence (with no duplicate term) where all the digits “1” are separated by two digits.


0



1, 2, 3, 10, 4, 12, 5, 13, 6, 14, 7, 15, 8, 16, 9, 17, 21, 20, 18, 31, 22, 19, 31, 23, 100, 102, 103, 104, 105, 106, 107, 108, 109, 120, 122, 123, 124, 125, 126, 127, 128, 129, 130, 132, 133, 134, 135, 136, 137, 138, 139, 140, 142, 143, 144, 145, 146, 147, 148, 149, 150
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OFFSET

1,2


COMMENTS

The sequence is started with a(1)=1 and always extended with the smallest integer not yet used that does not lead to a contradiction.


LINKS

Table of n, a(n) for n=1..61.


EXAMPLE

To match the infinite digitpattern 1..1..1..1..1..1.. (etc.) one must use the integer 10 after the third term (which is 3), then use the integer 4, then use the integer 12 (as 11 is forbidden: no integer with consecutive 1’s is allowed), etc.


CROSSREFS

Sequence in context: A307591 A031275 A306465 * A274299 A119023 A213962
Adjacent sequences: A276101 A276102 A276103 * A276105 A276106 A276107


KEYWORD

nonn,base


AUTHOR

Eric Angelini, Aug 18 2016


STATUS

approved



