

A282665


The larger term of the pair (a(n), a(n+1)) is always even and the larger digit of any pair of adjacent digits is also even.


2



0, 2, 1, 4, 3, 6, 5, 8, 7, 80, 20, 22, 12, 14, 16, 18, 24, 21, 26, 28, 34, 36, 38, 40, 42, 41, 44, 43, 46, 48, 56, 58, 60, 62, 61, 64, 63, 66, 65, 68, 78, 82, 81, 84, 83, 86, 85, 88, 87, 800, 200, 202, 120, 204, 121, 206, 122, 124, 126, 128, 140, 208, 141, 212, 142, 144, 143, 400, 214, 146, 148, 160, 216, 161, 218, 162, 164, 163
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OFFSET

1,2


COMMENTS

The sequence is started with a(1) = 0 and always extended with the smallest integer not yet present and not leading to a contradiction. If two successive digits are equal (e.g., 2,2) we accept that there is a "larger one" (2).


LINKS

JeanMarc Falcoz, Table of n, a(n) for n = 1..10001


EXAMPLE

In the 1st pair of integers (0,2) the larger term is (2), which is even;
in the 2nd pair of integers (2,1) the larger term is (2), which is even;
in the 3rd pair of integers (1,4) the larger term is (4), which is even;
in the 4th pair of integers (4,3) the larger term is (4), which is even;
...
in the 9th pair of integers (7,80) the larger term is (80), which is even;
in the 10th pair of integers (80,20) the larger term is (80), which is even;
in the 11th pair of integers (20,22) the larger term is (22), which is even; etc.
In the 1st pair of digits (0,2) the larger digit is (2), which is even;
in the 2nd pair of digits (2,1) the larger digit is (2), which is even;
in the 3rd pair of digits (1,4) the larger digit is (4), which is even;
in the 4th pair of digits (4,3) the larger digit is (4), which is even;
...
in the 9th pair of digits (7,8) the larger digit is (8), which is even;
in the 10th pair of digits (8,0) the larger digit is (8), which is even;
in the 11th pair of digits (0,2) the larger digit is (2), which is even; etc.


CROSSREFS

Cf. A282664 (odd rather than even).
Sequence in context: A026234 A317630 A282651 * A320283 A232805 A073672
Adjacent sequences: A282662 A282663 A282664 * A282666 A282667 A282668


KEYWORD

nonn,base


AUTHOR

Eric Angelini and JeanMarc Falcoz, Feb 20 2017


STATUS

approved



