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A261994 Number of complemented lattices on n nodes. 0
1, 1, 1, 0, 1, 2, 6, 18, 71, 307, 1594, 9446, 63461 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,6

REFERENCES

R. Belohlavek, V. Vychodil, Residual lattices of size <=12, Order 27 (2010) 147-161 doi:10.1007/s11083-010-9143-7, Table 6

LINKS

Table of n, a(n) for n=0..12.

PROG

(Sage)

for n in range(7):

    print(len([L for L in Posets(n) if L.is_lattice() and LatticePoset(L).is_complemented()]))

CROSSREFS

Sequence in context: A060181 A131281 A264036 * A177472 A194088 A022491

Adjacent sequences:  A261991 A261992 A261993 * A261995 A261996 A261997

KEYWORD

nonn,more

AUTHOR

Jori Mäntysalo, Sep 08 2015

STATUS

approved

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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)