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A325304
Irregular triangle read by rows: T(n,k) is the number of connected graphs on n unlabeled nodes with matching number k, (0 <= k <= floor(n/2)).
2
1, 1, 0, 1, 0, 2, 0, 1, 5, 0, 1, 20, 0, 1, 16, 95, 0, 1, 22, 830, 0, 1, 29, 790, 10297, 0, 1, 37, 1479, 259563, 0, 1, 46, 2625, 166988, 11546911
OFFSET
0,6
LINKS
Eric Weisstein's World of Mathematics, Matching Number
FORMULA
T(2*n, n) = A218463(n).
EXAMPLE
Triangle begins:
1;
1;
0, 1;
0, 2;
0, 1, 5;
0, 1, 20;
0, 1, 16, 95;
0, 1, 22, 830;
0, 1, 29, 790, 10297;
0, 1, 37, 1479, 259563;
0, 1, 46, 2625, 166988, 11546911;
...
CROSSREFS
Columns k=2..3 are A243800, A243801.
Row sums are A001349.
Cf. A286951 (not necessarily connected).
Cf. A218463 (right diagonal, even terms).
Sequence in context: A209687 A108263 A244523 * A134433 A125183 A092583
KEYWORD
nonn,tabf,more
AUTHOR
Andrew Howroyd, Sep 05 2019
STATUS
approved