A321419 Number of n element multisets of the 30th roots of unity with zero sum.

1, 0, 15, 10, 120, 156, 760, 1350, 4350, 8770, 22896, 47610, 110110, 226260, 483180, 964696

Offset

0,3

Comments

Equivalently, the number of closed convex paths of length n whose steps are the 30th roots of unity up to translation. For even n, there will be 15 paths of zero area consisting of n/2 steps in one direction followed by n/2 steps in the opposite direction.

Links

Table of n, a(n) for n=0..15.

Crossrefs

Column k=15 of A321414.

Cf. A321418.

Sequence in context: A215236 A040212 A299316 * A013379 A013449 A013461

Adjacent sequences: A321416 A321417 A321418 * A321420 A321421 A321422

Keyword

nonn,more

Author

Andrew Howroyd, Nov 09 2018

Status

approved