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

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