OFFSET
0,12
COMMENTS
In the case that both m and n are odd a single vertex is not covered, otherwise the maximum matchings are perfect matchings.
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..527
Eric Weisstein's World of Mathematics, Maximum Independent Edge Set
Eric Weisstein's World of Mathematics, Rook Graph
FORMULA
T(n,m) = T(m,n).
EXAMPLE
Array begins:
======================================================
n\m | 0 1 2 3 4 5 6
----+-------------------------------------------------
0 | 1 1 1 1 1 1 1 ...
1 | 1 1 1 3 3 15 15 ...
2 | 1 1 2 4 16 56 376 ...
3 | 1 3 4 72 132 7020 17280 ...
4 | 1 3 16 132 2016 44928 1551744 ...
5 | 1 15 56 7020 44928 22615200 243319680 ...
6 | 1 15 376 17280 1551744 243319680 61903180800 ...
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Feb 21 2021
STATUS
approved