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A046911 Number of isomorphism classes of irreducible quasiorders with n labeled points. 1
1, 1, 2, 4, 14, 62, 373, 2722 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

REFERENCES

J. A. Wright, There are 718 6-point topologies, quasi-orderings and transgraphs, Notices Amer. Math. Soc., 17 (1970), p. 646, Abstract #70T-A106.

LINKS

Table of n, a(n) for n=0..7.

J. A. Wright, Letter to N. J. A. Sloane, Apr 06 1972, listing 18 sequences

CROSSREFS

Cf. A046912.

Sequence in context: A027740 A132880 A019537 * A089127 A132852 A132079

Adjacent sequences:  A046908 A046909 A046910 * A046912 A046913 A046914

KEYWORD

nonn,nice

AUTHOR

John A. Wright.

STATUS

approved

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Last modified February 23 21:20 EST 2020. Contains 332195 sequences. (Running on oeis4.)