The number of orders with thirteen elements
Tóm tắt
The number of non-isomorphic posets on 13 elements is P13=33,823,827,452
An announcement of this result was sent to the on July 4th, 1992.
. This extends our previous result P12 which constituted the greatest known value. A table enumerates the posets according to their number of relations.
Tài liệu tham khảo
C.Chaunier and N.Lygerōs (1992) Progrès dans l'énumération des posets, C. R. Acad. Sci. Paris 314, série I, 691–694.
J. C.Culberson and G. J. E.Rawlins (1991) New results from an algorithm for counting posets, Order 7, 361–374.
M. Erné, The number of partially ordered sets with more points than unrelated pairs, Discrete Math. (preprint).
R.Fraïssé and N.Lygerōs (1991) Petits posets: dénombrement, représentabilité par cercles et «compenseurs», C. R. Acad. Sci. Paris 313, série I, 417–420.
F. Le Lionnais (1983) Les nombres remarquables, Hermann.