A006824 - OEIS

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A006824

Number of connected regular bipartite graphs of degree 4 with 2n nodes.
(Formerly M3493)

1, 1, 4, 14, 129, 1980, 62611, 2806490, 158937213, 10773251972, 855658082615, 78558949838723, 8251166737356319, 982806379842257309, 131756174189661102281, 19748565896506014747623, 3289970433888731383271400, 605948436052375098046655323, 122796503871896458570959144266

(list; graph; refs; listen; history; text; internal format)

OFFSET

4,3

REFERENCES

CRC Handbook of Combinatorial Designs, 1996, p. 648.

I. A. Faradzev, Constructive enumeration of combinatorial objects, pp. 131-135 of Problèmes combinatoires et théorie des graphes (Orsay, 9-13 Juillet 1976). Colloq. Internat. du C.N.R.S., No. 260, Centre Nat. Recherche Scient., Paris, 1978.

H. Gropp, On tactical configurations, regular bipartite graphs and (v,k,even)-designs, Discr. Math., 155 (1996), 81-98.

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

LINKS

Table of n, a(n) for n=4..22.

B. D. McKay and E. Rogoyski, Latin squares of order ten, Electron. J. Combinatorics, 2 (1995) #N3.

M. Meringer, Tables of Regular Graphs

FORMULA

Inverse Euler transform of A333730. - Andrew Howroyd, Apr 03 2020

CROSSREFS

Column 4 of A008326.

Cf. A006823, A006825, A333730.

Sequence in context: A137048 A137056 A302021 * A333730 A344201 A254718