OFFSET

1,4

COMMENTS

A hexagonal board of edge-length 3, for example, is numbered spirally as:

.

17--18--19

/

16 6---7---8

/ / \

15 5 1---2 9

\ \ / /

14 4---3 10

\ /

13--12--11

.

In Glinski's hexagonal chess, a knight (N) can move to these (o) cells:

.

. . . . .

. . o o . .

. o . . . o .

. o . . . . o .

. . . . N . . . .

. o . . . . o .

. o . . . o .

. . o o . .

. . . . .

.

a(n) stays constant at 72085 for n >= 177 since 72085 is also the last cell visited by knight moves on a spirally numbered infinite hexagonal board, moving to the lowest unvisited cell at each step.

LINKS

Sangeet Paul, Table of n, a(n) for n = 1..200

Chess variants, Glinski's Hexagonal Chess

Wikipedia, Hexagonal chess - GliĆski's hexagonal chess

CROSSREFS

KEYWORD

nonn

AUTHOR

Sangeet Paul, Aug 22 2019

STATUS

approved