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A333825
Lexicographically earliest sequence of distinct positive integers, which when mapped onto a square spiral, gives a set without three distinct aligned points.
3
1, 2, 3, 4, 17, 20, 22, 27, 45, 48, 67, 79, 80, 131, 135, 174, 180, 194, 201, 209, 236, 254, 312, 319, 394, 523, 644, 656, 706, 711, 733, 765, 766, 845, 848, 921, 922, 935, 1034, 1051, 1219, 1292, 1310, 1330, 1399, 1410, 1546, 1589, 1674, 1792, 1816, 1863
OFFSET
1,2
COMMENTS
This sequence has similarities with A236266.
EXAMPLE
The first terms, mapped onto a square spiral, are:
*---*---*---*---*---*---*---*---*
| |
* *---*---*---*---*---*---* *
| | | |
67 * 17---*---*---*---* * *
| | | | | |
* * * *---4---3 * * *
| | | | | | | |
* * * * 1---2 * * *
| | | | | | |
* * 20 *---*---*---* 27 *
| | | | |
* * *--22---*---*---*---* *
| | |
* *---*--45---*---*--48---*---*
|
*---*---*---*---*---*--79--80---*
PROG
(C#) See Links section.
CROSSREFS
See A333835 and A333866 for a similar sequences.
Sequence in context: A333835 A178683 A111191 * A115891 A378417 A359230
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Apr 07 2020
STATUS
approved