A317105 Squares visited by a (1,3)-leaper on a spirally numbered board and moving to the lowest available unvisited square at each step, squares labelled >=0.

0, 26, 12, 4, 10, 6, 14, 8, 18, 2, 16, 32, 54, 84, 24, 28, 50, 46, 20, 38, 62, 94, 56, 86, 124, 48, 22, 40, 66, 34, 58, 88, 52, 30, 60, 36, 68, 42, 76, 112, 70, 44, 72, 106, 148, 100, 140, 188, 134, 180, 128, 90, 136, 96, 64, 104, 146, 98, 138, 92, 130, 176, 230

Offset

0,2

Comments

Board is numbered with the square spiral:

.

16--15--14--13--12

| |

17 4---3---2 11 .

| | | |

18 5 0---1 10 .

| | |

19 6---7---8---9 .

|

20--21--22--23--24--25

.

The sequence is finite: at step 3722, square 7080 is visited, after which there are no unvisited squares within one move.

Links

Daniël Karssen, Table of n, a(n) for n = 0..3722

Daniël Karssen, Figure showing the first 46 steps of the sequence

Daniël Karssen, Figure showing the complete sequence

Formula

a(n) = A317106(n+1) - 1.

Crossrefs

Cf. A317106, A317107.

Sequence in context: A040654 A034057 A070715 * A033346 A158605 A040653

Adjacent sequences: A317102 A317103 A317104 * A317106 A317107 A317108

Keyword

nonn,fini,full

Author

Daniël Karssen, Jul 24 2018, following a suggestion from N. J. A. Sloane, Jul 15 2018

Status

approved