A268606 Number of ways to trisect a hexagon with side length n exactly into three identical parts in a triangular lattice.

1, 5, 116, 15785, 11599297, 47212453928, 1100377983366327, 148568527921382084692

Offset

1,2

Links

Table of n, a(n) for n=1..8.

G. P. Jelliss, Dissected Hexagons, The Games and Puzzles Journal, Issue 22, January-April 2002.

Luca Petrone, Illustration showing a(3) = 116

Crossrefs

Cf. A257952, A271741, A271857.

Sequence in context: A230338 A156514 A319392 * A006221 A265977 A208387

Adjacent sequences: A268603 A268604 A268605 * A268607 A268608 A268609

Keyword

nonn,hard,more

Author

Luca Petrone, Feb 08 2016

Extensions

Added a(6) from Jelliss's website by Vaclav Kotesovec, Mar 03 2016

a(7)-a(8) from Andrew Howroyd, Apr 11 2016

Status

approved