A323472 On a spirally numbered square grid, with labels starting at 0, this is the number of the last cell that a (1,n) leaper reaches before getting trapped, or -1 if it never gets trapped.

-1, 2083, 7080, 10846, 25962, 22420, 202890, 142678, 252952, 188500, 257478, 604327, 667826, 57216, 115496, 231929, 203330, 283650, 426850, 153520, 231298, 142266, 236486, 149871, 204526, 215032, 285982, 188081, 153460, 128801, 213852, 202258, 94966, 224777

Offset

1,2

Comments

A (1,2) leaper is a chess knight.

a(2)-a(5) were computed by Daniël Karssen.

Links

Rémy Sigrist, Table of n, a(n) for n = 1..1000

Rémy Sigrist, Figure showing the complete figure for a (1, 624) leaper (where the color is function of the time)

Rémy Sigrist, C++ program for A323472

N. J. A. Sloane and Brady Haran, The Trapped Knight, Numberphile video (2019)

Prog

(C++) See Links section.

Crossrefs

The sequences involved in this set of related sequences are A316884, A316967, A316667, A316328, A317106, A317105, A317416, A317415, A317438, A317437, and A323469, A323470, A323471, A323472.

Sequence in context: A233088 A229909 A323813 * A224438 A323714 A343179

Adjacent sequences: A323469 A323470 A323471 * A323473 A323474 A323475

Keyword

sign

Author

N. J. A. Sloane, Jan 28 2019

Extensions

More terms from Rémy Sigrist, Jan 29 2019

Status

approved