A393836 Number of fixed polygiraffes with n cells.

1, 4, 28, 234, 2162, 21272, 218740, 2323730, 25314097, 281333756, 3177896808, 36382573326

Offset

1,2

Comments

A giraffe is a (1,4)-leaper. A polygiraffe is a set of squares in the 2-dimensional grid, connected by giraffe leaps. As usual, fixed means that we only identify forms that are translations of each other; for one-sided forms (A393837), translations and rotations are identified; for free forms (A393838), translations, rotations, and reflections are identified.

The first 9 terms agree with A093877 and A151830. See formula in A393390.

Links

Table of n, a(n) for n=1..12.

Wikipedia, Giraffe.

Crossrefs

Row 4 of A393390.

Cf. A030444 (polyknights), A093877 (polyzebras), A151830, A393837 (one-sided), A393838 (free), A393839, A394194 (polyantelopes).

Sequence in context: A046904 A030444 A093877 * A394194 A151830 A354693

Adjacent sequences: A393833 A393834 A393835 * A393837 A393838 A393839

Keyword

nonn,more

Author

Pontus von Brömssen, Mar 02 2026

Status

approved