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 A244704 Number of n-node unlabeled rooted trees with thinning limbs and root outdegree (branching factor) 3. 2
 1, 1, 3, 6, 13, 25, 55, 107, 224, 454, 938, 1916, 3969, 8163, 16918, 35010, 72724, 151093, 314749, 656115, 1370348, 2864948, 5998547, 12572884, 26385837, 55431031, 116577538, 245415158, 517152607, 1090771973, 2302729115, 4865449045, 10288826434, 21774842539 (list; graph; refs; listen; history; text; internal format)
 OFFSET 4,3 COMMENTS In a rooted tree with thinning limbs the outdegree of a parent node is larger than or equal to the outdegree of any of its child nodes. LINKS Alois P. Heinz, Table of n, a(n) for n = 4..1000 FORMULA a(n) ~ c * d^n / n^(3/2), where d = 2.1991393868..., c = 1.0259536... . - Vaclav Kotesovec, Aug 27 2014 EXAMPLE a(7) = 6:     o       o        o      o        o       o    /|\     /|\      /|\    /|\     / | \    /|\   o o o   o o o    o o o  o o o   o  o  o  o o o   |      ( )      /|\     | |    ( ) |     | | |   o      o o     o o o    o o    o o o     o o o   |      |                |   o      o                o   |   o MAPLE b:= proc(n, i, h, v) option remember; `if`(n=0,       `if`(v=0, 1, 0), `if`(i<1 or v<1 or n b(n-1\$2, 3\$2): seq(a(n), n=4..50); CROSSREFS Column k=3 of A244657. Sequence in context: A121349 A215984 A074890 * A032198 A079941 A255125 Adjacent sequences:  A244701 A244702 A244703 * A244705 A244706 A244707 KEYWORD nonn AUTHOR Alois P. Heinz, Jul 04 2014 STATUS approved

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Last modified November 16 06:50 EST 2018. Contains 317258 sequences. (Running on oeis4.)