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A332760
Triangle of number of connected graphs with n>=2 nodes and maximum degree 1<=k<n.
2
1, 0, 2, 0, 2, 4, 0, 2, 8, 11, 0, 2, 27, 49, 34, 0, 2, 62, 289, 344, 156, 0, 2, 192, 1735, 4457, 3687, 1044, 0, 2, 529, 11676, 63493, 109623, 63411, 12346, 0, 2, 1731, 87669, 1067440, 3835541, 4540334, 1909186, 274668, 0, 2
OFFSET
2,3
FORMULA
T(n,n-1) = A000088(n-1).
T(n,2) = 2 for n>2 as the only possibilities are a cycle graph or a path graph.
EXAMPLE
Triangle starts
1;
0, 2;
0, 2, 4;
0, 2, 8, 11;
0, 2, 27, 49, 34;
0, 2, 62, 289, 344, 156;
0, 2, 192, 1735, 4457, 3687, 1044;
0, 2,...
CROSSREFS
Cf. A263293, A001349 (row sums), A000088.
Sequence in context: A061930 A209691 A221683 * A199335 A141660 A368500
KEYWORD
nonn,tabl,more
AUTHOR
Henry Bottomley, Feb 22 2020
EXTENSIONS
a(32)-a(48) from Chai Wah Wu, Sep 08 2020
STATUS
approved