A381489 Index of first half of decomposition of integers into pairs x(i)+y(j) based on A380008 and A380009, respectively.

0, 0, 1, 1, 2, 2, 3, 3, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 4, 4, 5, 5, 6, 6, 7, 7, 0, 0, 1, 1, 2, 2, 3, 3, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 4, 4, 5, 5, 6, 6, 7, 7, 0, 0, 1, 1, 2, 2, 3, 3, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 4, 4, 5, 5, 6, 6, 7, 7

Offset: 0

Author

Luis Rato, Feb 25 2025

Keywords

• easy
• nonn

Comments

One coordinate of a recursive non-self-intersecting walk on the square lattice Z^2.

Every integer appears infinitely many times in the sequence.

Examples

			A380008(a(14)) + A380009(A381490(14)) = A380008(3) + A380009(2) = 6+8 = 14.
		

Links

• Luis Rato, Plot of an NZ-order curve, containing the integers from 0 to 255.
• Index entries for sequences related to coordinates of 2D curves

Crossrefs

Cf. A380008, A380009, A381490.

Formula

n = A380008(a(n)) + A380009(A381490(n)).