A358566 Number of distinct spans of length n with no 3-term arithmetic progression, containing zero, and with maximum element smallest possible.

1, 1, 2, 1, 4, 7, 6, 1, 2, 2, 2, 1, 2, 2, 20, 1, 14, 2, 2, 2, 4

Offset: 1

Author

Joshua Zelinsky, Nov 22 2022

Keywords

• nonn
• more

Comments

Offset by 1 from the same function in the referenced paper, which does not include zero in their count of how long spans are for the "well-spaced rows".

Examples

			a(5)=4 since we have as possible spans 0,1,3,7,8; 0,1,5,6,8; 0,1,5,7,8; 0,2,3,7,8. (It is easy to check that if the maximum term is 7 or lower then there must be fewer than 5 elements in the sequence.)
		

Links

• Noam Benson-Tilsen, Samuel Brock, Brandon Faunce, Monish Kumar, Noah Dokko Stein, and Joshua Zelinsky, Total Difference Labeling of Regular Infinite Graphs, arXiv:2107.11706 [math.CO], 2021-2022.

Crossrefs

Cf. A005047.