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A006427 Number of rooted toroidal maps.
(Formerly M5105)
0
20, 1071, 26320, 431739, 5494896, 58677420, 550712668, 4681144391 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

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

Walsh, T. R. S.; Lehman, A. B.; Counting rooted maps by genus. III: Nonseparable maps. J. Combinatorial Theory Ser. B 18 (1975), 222-259.

LINKS

Table of n, a(n) for n=1..8.

CROSSREFS

Sequence in context: A128476 A160132 A138915 * A072962 A224125 A324416

Adjacent sequences:  A006424 A006425 A006426 * A006428 A006429 A006430

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified December 16 06:18 EST 2019. Contains 330016 sequences. (Running on oeis4.)