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A327460
Lexicographically earliest infinite sequence of distinct positive integers such that for every k >= 1, all the k(k+1)/2 numbers in the triangle of differences of the first k terms are distinct.
15
1, 3, 9, 5, 12, 10, 23, 8, 22, 17, 42, 16, 43, 20, 38, 26, 45, 32, 65, 28, 64, 39, 76, 34, 81, 48, 98, 40, 92, 54, 109, 60, 116, 51, 114, 58, 117, 70, 136, 67, 135, 71, 145, 72, 147, 69, 146, 80, 164, 87, 166, 82, 170, 108, 198, 101
OFFSET
1,2
COMMENTS
This is an infinite version of A327762. The first 55 terms are the same as in A327762.
Inspired by A327743.
The usual topological arguments show that there IS a sequence satisfying the definition. So far, the terms of A327460 lie on two roughly straight lines, of slopes about 1.75 and 3.5: see A328069, A328070. - N. J. A. Sloane, Oct 07 2019
If only the first differences are constrained, one gets the classical Mian-Chowla sequence A005282. - M. F. Hasler, Oct 09 2019. See also another classic, A005228, and A328190. - N. J. A. Sloane, Nov 01 2019
EXAMPLE
The difference triangle of the first k=8 terms of the sequence is
1, 3, 9, 5, 12, 10, 23, 8, ...
2, 6, -4, 7, -2, 13, -15, ...
4, -10, 11, -9, 15, -28, ...
-14, 21, -20, 24, -43, ...
35, -41, 44, -67, ...
-76, 85, -111, ...
161, -196, ...
-357, ...
All 8*9/2 = 36 numbers are distinct.
CROSSREFS
See also A327458 (differences), A328066 (sorted), A328067, A328068 (complement), A328069 and A328070 (bisections), A328071; A235538 (absolute differences distinct).
The inverse binomial transform is A327459.
Sequence in context: A077383 A084492 A327762 * A084496 A084530 A070355
KEYWORD
nonn,nice
AUTHOR
N. J. A. Sloane, Sep 25 2019
STATUS
approved