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A006926
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Number of connected trivalent graphs with 2n nodes and girth exactly 6.
(Formerly M3969)
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14
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0, 0, 0, 0, 0, 0, 0, 1, 1, 5, 32, 385, 7573, 181224, 4624480, 122089998, 3328899586, 93988909755
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listen;
history;
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OFFSET
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0,10
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REFERENCES
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CRC Handbook of Combinatorial Designs, 1996, p. 647.
Gordon Royle, personal communication.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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EXTENSIONS
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Definition corrected to include "connected", and "girth at least 6" minus "girth at least 7" formula provided by Jason Kimberley, Dec 12 2009
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STATUS
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approved
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