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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.
7
-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, Figure showing the complete figure for a (1, 624) leaper (where the color is function of the time)
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
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Jan 28 2019
EXTENSIONS
More terms from Rémy Sigrist, Jan 29 2019
STATUS
approved