A394194 Number of fixed polyantelopes with n cells.

1, 4, 28, 234, 2162, 21272, 218740, 2323730, 25314097, 281345096, 3178474308, 36400646766, 421693622520, 4933617241664

Offset

1,2

Comments

An antelope is a (3,4)-leaper. A polyantelope is a set of squares in the 2-dimensional grid, connected by antelope leaps. As usual, fixed means that we only identify forms that are translations of each other; for one-sided forms (A394195), translations and rotations are identified; for free forms (A394196), translations, rotations, and reflections are identified.

a(14) was found by John Mason.

Links

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

Wikipedia, Fairy chess piece.

Formula

a(n) = A151830(n) for 1 <= n <= 13. (See formula in A393390.)

Crossrefs

Row 5 of A393390.

Cf. A030444 (polyknights), A093877 (polyzebras), A151830, A393836 (polygiraffes), A394195 (one-sided), A394196 (free), A394197.

Sequence in context: A030444 A093877 A393836 * A151830 A354693 A112113

Adjacent sequences: A394191 A394192 A394193 * A394195 A394196 A394197

Keyword

nonn,more

Author

Pontus von Brömssen, Mar 12 2026

Status

approved