A390998 Number of fixed polyaboloes (or polytans) with n cells, where two triangles sharing a hypotenuse (making up a square) are counted as a single cell.

5, 18, 90, 510, 3087, 19424, 125442, 826622, 5532723, 37492330, 256611656, 1770847429, 12304993349, 86006708200

Offset

1,1

Comments

See A390996 for illustrations.

Links

Table of n, a(n) for n=1..14.

Crossrefs

Cf. A353978, A390995, A390996 (free), A390997 (one-sided), A391001.

Sequence in context: A009305 A097574 A113023 * A174082 A188329 A165962

Adjacent sequences: A390995 A390996 A390997 * A390999 A391000 A391001

Keyword

nonn,more

Author

Pontus von Brömssen, Nov 27 2025

Extensions

a(13)-a(14) from John Mason, Dec 02 2025

Status

approved