A389961 a(n) is the number of edges in the graph PG(n) with one node for each free n-celled polyiamond and edges between nodes corresponding to polyiamonds that can be obtained from each other by moving one cell, where the intermediate polyform (the set of cells remaining when the cell to be moved is detached) is not required to be a connected polyiamond.

0, 0, 0, 3, 5, 41, 142, 601, 1968, 6982, 22619, 74693, 239838, 773453, 2466183, 7864541, 24948440

Offset

1,4

Links

Table of n, a(n) for n=1..17.

Crossrefs

Cf. A000577, A389962, A389963, A389964, A098891.

Sequence in context: A120265 A158328 A389964 * A258933 A060433 A216085

Adjacent sequences: A389958 A389959 A389960 * A389962 A389963 A389964

Keyword

nonn,more

Author

John Mason, Oct 21 2025

Status

approved