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A048143 Number of labeled connected simplicial complexes with n nodes. +0
2
1, 1, 1, 5, 84, 6348, 7743728, 2414572893530, 56130437190053299918162 (list; graph; listen)
OFFSET

0,4

COMMENT

Also number of connected antichains on a labeled n-set.

EXAMPLE

For n=3 we could have 2 edges (in 3 ways), 3 edges (1 way), or 3 edges and a triangle (1 way), so a(3)=5.

a(5) = 1+75+645+1655+2005+1345+485+115+20+2 = 6348, cf. A094033, A094034, A094035, A094036,A094037.

CROSSREFS

Cf. A006126.

Cf. A120338.

Adjacent sequences: A048140 A048141 A048142 this_sequence A048144 A048145 A048146

Sequence in context: A006471 A061628 A111911 this_sequence A137083 A121290 A012743

KEYWORD

nonn,nice,more

AUTHOR

Greg Huber, 12 May 1983

EXTENSIONS

More terms from Vladeta Jovovic (vladeta(AT)Eunet.yu), Jun 17 2006

Entry revised by njas, Jul 27 2006

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Last modified October 6 16:13 EDT 2008. Contains 144667 sequences.


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