A271858 Number of ways to trisect a triangle with side length n exactly into three identical parts in a triangular lattice.

0, 1, 1, 2, 5, 20, 56, 276, 2136, 13756, 148352, 2727448, 41044816, 1056334024, 46033137324

Offset: 1

Author

Andrew Howroyd, Apr 15 2016

Keywords

• nonn
• more

Comments

In the case that n is not divisible by 3 the central triangle is removed, otherwise the dissection would not be possible.

Links

• G. P. Jelliss, Trisected Triangles, The Games and Puzzles Journal, Issue 22, January-April 2002.

Crossrefs

Cf. A268606, A271857, A113900, A257952.