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A319372
Triangle read by rows: T(n,k) is the number of Cayley graphs with n nodes and valency k, (0 <= k < n).
4
1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 2, 2, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 2, 3, 3, 2, 1, 1, 1, 0, 2, 0, 3, 0, 2, 0, 1, 1, 1, 2, 2, 4, 4, 2, 2, 1, 1, 1, 0, 1, 0, 2, 0, 2, 0, 1, 0, 1, 1, 1, 4, 7, 11, 13, 13, 11, 7, 4, 1, 1, 1, 0, 1, 0, 3, 0, 4, 0, 3, 0, 1, 0, 1
OFFSET
1,18
COMMENTS
First differs from A319367 in row 10.
LINKS
Gordon Royle, Transitive Graphs
Eric Weisstein's World of Mathematics, Cayley Graph
Wikipedia, Cayley graph
EXAMPLE
Triangle begins, n >= 1, 0 <= k < n:
1;
1, 1;
1, 0, 1;
1, 1, 1, 1;
1, 0, 1, 0, 1;
1, 1, 2, 2, 1, 1;
1, 0, 1, 0, 1, 0, 1;
1, 1, 2, 3, 3, 2, 1, 1;
1, 0, 2, 0, 3, 0, 2, 0, 1;
1, 1, 2, 2, 4, 4, 2, 2, 1, 1;
1, 0, 1, 0, 2, 0, 2, 0, 1, 0, 1;
1, 1, 4, 7, 11, 13, 13, 11, 7, 4, 1, 1;
1, 0, 1, 0, 3, 0, 4, 0, 3, 0, 1, 0, 1;
1, 1, 2, 3, 6, 6, 9, 9, 6, 6, 3, 2, 1, 1;
1, 0, 3, 0, 7, 0, 11, 0, 11, 0, 7, 0, 3, 0, 1;
1, 1, 3, 7, 15, 26, 39, 47, 47, 39, 26, 15, 7, 3, 1, 1;
1, 0, 1, 0, 4, 0, 7, 0, 10, 0, 7, 0, 4, 0, 1, 0, 1;
1, 1, 4, 7, 16, 23, 38, 45, 53, 53, 45, 38, 23, 16, 7, 4, 1, 1;
...
CROSSREFS
Column k=3 is aerated A319374.
Row sums are A185959.
Sequence in context: A263087 A204433 A004578 * A319367 A234514 A343453
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Sep 17 2018
STATUS
approved