

A103938


Number of rooted nonseparable nedge maps in the plane (planar with a distinguished outside face).


1



3, 2, 5, 18, 77, 364, 1836, 9690, 52877, 296010, 1690845, 9817080, 57769740, 343806368, 2065802056, 12515350122, 76367432013, 468922828150, 2895381678735, 17966214519330
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OFFSET

1,1


REFERENCES

V. A. Liskovets and T. R. Walsh, Enumeration of unrooted maps on the plane, Rapport technique, UQAM, No. 200501, Montreal, Canada, 2005.


LINKS

Table of n, a(n) for n=1..20.
V. A. Liskovets and T. R. Walsh, Counting unrooted maps on the plane, Advances in Applied Math., 36, No.4 (2006), 364387.


FORMULA

a(n)=(n+2)*A000139(n)/2.


CROSSREFS

Sequence in context: A187943 A214502 A077039 * A085973 A005265 A005266
Adjacent sequences: A103935 A103936 A103937 * A103939 A103940 A103941


KEYWORD

easy,nonn


AUTHOR

Valery A. Liskovets, Mar 17 2005


STATUS

approved



