A378343 Number of n edge connected unsensed planar maps with an external face in which all internal faces are triangles.

1, 0, 1, 2, 1, 4, 7, 10, 22, 41, 77, 167, 349, 736, 1642, 3627, 8120, 18575, 42548, 97871, 228166, 532484, 1246778, 2941748, 6952421, 16470326, 39217775, 93530974, 223542903, 536138078, 1287943658, 3099775046, 7479610688, 18075710749, 43755189158, 106127886654, 257778445136

Offset

3,4

Links

Andrew Howroyd, Table of n, a(n) for n = 3..100

Formula

a(n) = (A378338(n) + A378342(n))/2.

Prog

(PARI) A378343seq(30) \\ See PARI link in A378340 for program code.

Crossrefs

Antidiagonal sums of A378103.

Cf. A377785 (by vertices), A378338 (sensed), A378342 (achiral).

Sequence in context: A139769 A357470 A326894 * A275778 A007839 A364658

Adjacent sequences: A378340 A378341 A378342 * A378344 A378345 A378346

Keyword

nonn

Author

Andrew Howroyd, Nov 25 2024

Status

approved