A378341 - OEIS

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A378341

Number of connected achiral planar maps with an external face and n internal triangular faces.

1, 2, 6, 16, 45, 129, 367, 1081, 3098, 9291, 26788, 81341, 235729, 722479, 2102856, 6492146, 18965527, 58898531, 172600126, 538640825, 1582733185, 4959648919, 14607576158, 45935431662, 135571479679, 427621459608, 1264356405112, 3998682343629, 11842126315245, 37540318975749

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

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..30.

PROG

(PARI) A378341seq(30) \\ See PARI link in A378340 for program code.

CROSSREFS

Column sums of A378340.

Cf. A378337, A378339, A378342.

Sequence in context: A333106 A025266 A074403 * A337318 A333070 A290953

Adjacent sequences: A378338 A378339 A378340 * A378342 A378343 A378344

KEYWORD

nonn

AUTHOR

Andrew Howroyd, Nov 25 2024

STATUS

approved