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A218553
Order of (5,n) cage, i.e., minimal order of 5-regular graph of girth n.
7
6, 10, 30, 42
OFFSET
3,1
COMMENTS
a(7) <= 152, a(8) = 170, a(12) = 2730. - From Royle's page via Jason Kimberley, Dec 21 2012
LINKS
Andries E. Brouwer, Cages
G. Exoo and R. Jajcay, Dynamic cage survey, Electr. J. Combin. (2008, 2011).
Eric Weisstein's World of Mathematics, Cage Graph (claims too much)
FORMULA
a(n) >= A061547(n+1).
CROSSREFS
Orders of cages: A054760 (n,k), A000066 (3,n), A037233 (4,n), this sequence (5,n), A218554 (6,n), A218555 (7,n), A191595 (n,5).
Sequence in context: A271412 A272278 A272508 * A265857 A256865 A163478
KEYWORD
hard,more,nonn
AUTHOR
EXTENSIONS
a(7) deleted by Jason Kimberley, Dec 21 2012
STATUS
approved