A392939 Number of free polyquoins with n cells.

1, 3, 35, 1098, 49023, 2518518, 135971708

Offset

1,2

Comments

A polyquoin (term coined by George Sicherman) is like a polycube, but the cells can be joined across a complete, half or quarter-face, like a three-dimensional polynar.

Links

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

George Sicherman, Catalogue of Polyquoins.

Crossrefs

Cf. A038119, A390620, A392940 (one-sided), A392941 (fixed).

Sequence in context: A107712 A062699 A012767 * A279377 A215582 A136525

Adjacent sequences: A392936 A392937 A392938 * A392940 A392941 A392942

Keyword

nonn,more,hard

Author

John Mason, Jan 27 2026

Extensions

Terms a(1)-a(6) confirmed by George Sicherman.

Status

approved