A308748 a(n) is the maximum number of pentagonal polyiamond divisions of an equilateral triangle of order n when tiling with the two smallest pentagonal polyiamonds.

0, 0, 0, 0, 0, 0, 9, 12, 15, 18, 23, 28, 32, 38, 44, 50, 57

Offset

1,7

Comments

The two smallest pentagonal polyiamonds contain five and six unit triangles. All internal angles are either 60, 120 or 240 degrees.

Order five and six equilateral triangle pentagonal tilings require pentagonal tiles larger than hexiamonds.

Links

Table of n, a(n) for n=1..17.

Craig Knecht, Close necks type 1 and type 2.

Craig Knecht, Close neck cluster tiling.

Craig Knecht, Close neck sphinx tile clusters.

Craig Knecht, Example for the sequence.

Craig Knecht, Neck connected pathways.

Craig Knecht, Pentagonal tiling of T5, T6.

Craig Knecht, Tiling with larger pentagonals.

Walter Trump, Number of positions of a polyiamond tile in a triangle frame.

Walter Trump, Pentagonal polyiamonds.

Crossrefs

Cf. A002061.

Sequence in context: A365408 A161345 A102655 * A120167 A263674 A337701

Adjacent sequences: A308745 A308746 A308747 * A308749 A308750 A308751

Keyword

nonn,more

Author

Craig Knecht, Jun 21 2019

Status

approved