A378343 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

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).