A057782 Building block is trapezoid formed from 3 equilateral triangles; sequence gives number of pieces (polytraps) that can be formed from n such trapezoids.

1, 9, 94, 1552, 27285, 509805, 9783124

Offset

1,2

Comments

Also known as "Polytriamonds" because the building block is the unique triamond (composite of three equilateral triangles joined edge-to-edge). - Aaron N. Siegel, May 23 2022

References

Computed by Brendan Owen.

Links

Table of n, a(n) for n=1..7.

Abaroth's World, Polyhes, Polyhalfhexes & Polytriamonds

Andrew Clarke, Other Polyforms

Crossrefs

Cf. A000577, A000228, A000105, A056844.

Sequence in context: A048359 A307961 A099297 * A115071 A000562 A193216

Adjacent sequences: A057779 A057780 A057781 * A057783 A057784 A057785

Keyword

nonn,nice,hard,more

Author

N. J. A. Sloane, Oct 29 2000

Extensions

Link updated by William Rex Marshall, Dec 16 2009

a(7) from Aaron N. Siegel, May 23 2022

Status

approved