A325606 Lower left-hand x-coordinate for 4 X 4 invisible forest with 0 < x < y.

7247643, 6349914, 13449225, 3268473, 16799913, 12209988, 7676094, 25869732, 27330093, 19113828, 3689958, 8579373, 35193585, 10557390, 31662993, 40976505, 20262723, 47516988, 12932424, 10792494, 13027728, 24801060, 44040840, 37959282, 42196362, 16439577, 43732038

Offset: 1

Author

Benjamin Hutz, May 31 2019

Keywords

• nonn

Comments

These are 4 X 4 rectangles of lattice points not visible along straight lines of sight from the origin. The sequence is ordered by Euclidean distance from (0,0).

Examples

			(7247643, 10199370), (6349914, 13125369), (13449225, 13458288), (3268473, 21374352), (16799913, 22339875)
		

Links

• E. Goins, P. Harris, B. Kubik, A. Mbirika, Lattice Point Visibility on Generalized Lines of Sight, arXiv:1710.04554 [math.NT], 2017; Amer. Math. Monthly 125 (2018) 593-601.
• F. Herzog, B. M. Stewart, Patterns of Visible and Nonvisible Lattice Points, Amer. Math. Monthly 78 (1971) 487-496
• S. Laishram, F. Luca, Rectangles Of Nonvisible Lattice Points, J. Int. Seq. 18 (2015) 15.10.8.

Crossrefs

Cf. A157426, A157427, A157428, A157429.

Cf. A325602, A325603, A325604, A325605, A325607.

Extensions

a(6)-a(27) from Giovanni Resta, Jun 05 2019