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A005977 Reduced interval graphs with n nodes.
(Formerly M1787)
0
0, 0, 0, 0, 1, 2, 7, 31, 168, 1025, 7013, 52495, 425213, 3696032, 34291937, 338161526, 3532185118, 38963334652, 452704892533, 5526901638291, 70746674291507 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

REFERENCES

P. J. Hanlon, personal communication.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Table of n, a(n) for n=1..21.

Phil Hanlon, Counting interval graphs, Trans. Amer. Math. Soc. 272 (1982), no. 2, 383-426.

CROSSREFS

Sequence in context: A193657 A007164 A321208 * A199675 A059037 A245313

Adjacent sequences:  A005974 A005975 A005976 * A005978 A005979 A005980

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified December 14 02:56 EST 2018. Contains 318087 sequences. (Running on oeis4.)