A378334 Number of n-node connected sensed planar maps with an external face, whose internal faces are triangles and which is rooted at a node on the external face.

1, 3, 16, 88, 537, 3473, 23562, 165859, 1202919, 8941118, 67836666, 523722889, 4104244351, 32583588994, 261635413752, 2122002356439, 17364496928654, 143230857011191, 1189928600338968, 9949848535116510, 83688384576105358, 707689149415139246, 6013842677410501394

Offset

3,2

Links

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

Example

The a(4) = 3 rooted planar maps are:
    R---o    R---o      R-----o
    | \ |    | / |      | \ / |
    o---o    o---o       \ o /
                          \|/
                           o

Prog

(PARI) A378334seq(25) \\ See PARI link in A378340 for program code

Crossrefs

Cf. A377785, A378335, A378339, A378340.

Sequence in context: A163604 A151329 A356402 * A347930 A026111 A026330

Adjacent sequences: A378331 A378332 A378333 * A378335 A378336 A378337

Keyword

nonn

Author

Andrew Howroyd, Nov 23 2024

Status

approved