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A193489 Number of rooted trees with n nodes and omega-valency 4. 6
0, 0, 0, 0, 0, 1, 1, 7, 13, 55, 127, 435, 1110, 3458, 9261, 27460, 75305, 217619, 603618, 1720712, 4799095, 13580179, 37979149, 107045222, 299800569, 843242264, 2363693561, 6641675073, 18628827667, 52325428340 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

COMMENTS

See A003120 for definitions.

LINKS

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

J.-C. Arditti, Dénombrement des arborescences dont le graphe de comparabilité est Hamiltonien, Discrete Math., 5 (1973), 189-200.

CROSSREFS

Cf. A003120, A193487, A193489, A193490, A193491.

Sequence in context: A108056 A018562 A112540 * A091005 A015441 A255286

Adjacent sequences:  A193486 A193487 A193488 * A193490 A193491 A193492

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jul 27 2011

STATUS

approved

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Last modified November 27 15:11 EST 2020. Contains 338683 sequences. (Running on oeis4.)