A378339 Number of n-node connected achiral planar maps with an external face in which all internal faces are triangles.

1, 2, 5, 15, 46, 139, 449, 1448, 4799, 15971, 54107, 184048, 633365, 2188644, 7624153, 26659774, 93772014, 330946542, 1173233805, 4171572088, 14884905583, 53249784377, 191043396323, 686956509123, 2476044740337, 8942288625630, 32360306616473, 117309644377341

Offset

3,2

Links

Andrew Howroyd, Table of n, a(n) for n = 3..200

Prog

(PARI) A378339seq(30) \\ See PARI link in A378340 for program code.

Crossrefs

Row sums of A378340.

Cf. A377785 (unsensed), A378335 (sensed), A378341 (by faces), A378342 (by edges).

Sequence in context: A287582 A122392 A139782 * A047086 A071731 A360272

Adjacent sequences: A378336 A378337 A378338 * A378340 A378341 A378342

Keyword

nonn

Author

Andrew Howroyd, Nov 24 2024

Status

approved