id:A030982 - OEIS Search Results

Search: id:A030982

Displaying 1-1 of 1 results found.

page 1

Noncrossing nonplanted bushes with n nodes, i.e. rooted noncrossing trees with n nodes and no nodes of degree 1.

+0
1

0, 1, 1, 7, 18, 80, 284, 1169, 4628, 19137, 79165, 333058, 1410608, 6029816, 25941384, 112315945, 488862888, 2138161043, 9391903131, 41414729419, 183264846010, 813564012660, 3622193670040, 16170171489820 (list; graph; listen)

	OFFSET	`1,4`
	LINKS	`Index entries for sequences related to rooted trees`
	FORMULA	`5sum((-1)^(n-k)2^(n-k)kbinomial(n, k)binomial(3k-2, k-2)/(2*k+1), k=2..n)/n.`
	CROSSREFS	`A030981-A030980.` `Sequence in context: A084819 A019534 A024830 this_sequence A156238 A156295 A070414` `Adjacent sequences: A030979 A030980 A030981 this_sequence A030983 A030984 A030985`
	KEYWORD	`nonn`
	AUTHOR	`Emeric Deutsch (deutsch(AT)duke.poly.edu)`

page 1

Search completed in 0.002 seconds

Last modified November 25 08:46 EST 2009. Contains 167481 sequences.

AT&T Labs Research