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A157016 Number of graphs with n vertices such that a bipartite connected component doesn't exist. 2
1, 0, 0, 1, 3, 16, 96, 812, 10957, 260494, 11713772, 1006689871, 164059928509, 50335918374222, 29003488479015273, 31397381309486933777, 63969560164056545231089, 245871831711240782887877980, 1787331725280384281389706209909, 24636021429463931875328533035140871, 645465483198968863672173418327800803328 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..20.

FORMULA

Euler transform of A157051. - Max Alekseyev, Feb 22 2009

A157015(n) + a(n) = A000088(n).

MATHEMATICA

cbs[g_] := Or @@ Map[BipartiteQ, Map[InduceSubgraph[g, # ] &, ConnectedComponents[g]]] Table[Count[Map[cbs, ListGraphs[n]], False], {n, 6}]

Table[Count[Map[cbs, ListGraphs[n]], False], {n, 7}] (* Wouter Meeussen, Feb 21 2009 *)

CROSSREFS

Sequence in context: A000270 A157051 A000271 * A228792 A233203 A074553

Adjacent sequences:  A157013 A157014 A157015 * A157017 A157018 A157019

KEYWORD

nonn

AUTHOR

Tanya Khovanova, Feb 21 2009

EXTENSIONS

a(7) from Wouter Meeussen, Feb 21 2009

Formula and terms a(8)-a(17) from Max Alekseyev, Feb 22 2009

Corrected by Max Alekseyev and Vladeta Jovovic, May 02 2009

a(18)-a(20) from Max Alekseyev, Jun 24 2013

STATUS

approved

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Last modified August 18 14:27 EDT 2017. Contains 290720 sequences.