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A187236 Number of simple imperfect graphs on n vertices. 1
0, 0, 0, 0, 1, 8, 138, 3459, 137912, 8735904, 903185866, 159235673397, 50091451190693 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Table of n, a(n) for n=1..13.

Eric Weisstein's World of Mathematics, Imperfect Graph.

FORMULA

a(n) = A000088(n) - A052431(n).

CROSSREFS

Cf. A000088, A052431, A187237.

Sequence in context: A281684 A050789 A274669 * A301835 A091060 A092703

Adjacent sequences:  A187233 A187234 A187235 * A187237 A187238 A187239

KEYWORD

nonn,more,hard

AUTHOR

Eric W. Weisstein, Mar 07 2011

EXTENSIONS

a(13) from Alois P. Heinz, Aug 14 2019

STATUS

approved

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Last modified November 27 06:49 EST 2020. Contains 338678 sequences. (Running on oeis4.)