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A006402 Nonseparable planar maps with n edges.
(Formerly M0812)
1
1, 2, 3, 6, 16, 42, 151, 596, 2605, 12098, 59166, 297684, 1538590, 8109078, 43476751, 236474942, 1302680941, 7256842362, 40832979283, 231838418310, 1327095781740 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

COMMENTS

Some people begin this 2,1,2,3,6,..., others begin it 0,1,2,3,6,....

REFERENCES

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

T. R. S. Walsh, personal communication.

LINKS

Table of n, a(n) for n=2..22.

V. A. Liskovets, T. R. S. Walsh, The enumeration of nonisomorphic 2-connected planar maps, Canad. J. Math. 35 (1983), no. 3, 417-435.

Timothy R. Walsh, Generating nonisomorphic maps without storing them, SIAM J. Algebraic Discrete Methods 4 (1983), no. 2, 161-178.

T. R. S. Walsh, Number of sensed planar maps with n edges and m vertices

CROSSREFS

Sequence in context: A159341 A159342 A089872 * A284417 A219024 A145860

Adjacent sequences:  A006399 A006400 A006401 * A006403 A006404 A006405

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified December 11 07:18 EST 2019. Contains 329914 sequences. (Running on oeis4.)