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URL: https://oeis.org/A186717

⇱ A186717 - OEIS

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A186717
Irregular triangle C(n,k): the number of connected k-regular graphs on n vertices having girth at least seven.
11
1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 3, 0, 0, 1, 0, 0, 0, 1, 21, 0, 0, 1, 0, 0, 0, 1, 546, 0, 0, 1, 0, 0, 0, 1, 30368
OFFSET
1,74
EXAMPLE
1;
0, 1;
0, 0;
0, 0;
0, 0;
0, 0;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1;
0, 0, 1, 1;
0, 0, 1, 0;
0, 0, 1, 3;
0, 0, 1, 0;
0, 0, 1, 21;
0, 0, 1, 0;
0, 0, 1, 546;
0, 0, 1, 0;
0, 0, 1, 30368;
0, 0, 1, 0;
0, 0, 1, 1782840;
0, 0, 1, 0;
0, 0, 1, 95079083;
0, 0, 1, 0;
0, 0, 1, 4686063120;
0, 0, 1, 0;
CROSSREFS
Triangular arrays C(n,k) counting connected simple k-regular graphs on n vertices with girth at least g: A068934 (g=3), A186714 (g=4), A186715 (g=5), A186716 (g=6), this sequence (g=7), A186718 (g=8), A186719 (g=9).
Connected k-regular simple graphs with girth at least 7: A186727 (any k), this sequence (triangle); specific k: A185117 (k=2), A014375 (k=3).
Triangular arrays C(n,k) counting connected simple k-regular graphs on n vertices with girth exactly g: A186733 (g=3), A186734 (g=4).
Sequence in context: A192732 A092573 A307801 * A344833 A233286 A305802
KEYWORD
nonn,hard,tabf
AUTHOR
Jason Kimberley, Nov 28 2011
STATUS
approved