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A270246
Array read by antidiagonals: T(n,m) is the number of matchings in the torus grid graph C_n X C_m.
3
1, 2, 2, 4, 7, 4, 7, 32, 32, 7, 11, 108, 370, 108, 11, 18, 342, 2764, 2764, 342, 18, 29, 1104, 19874, 41025, 19874, 1104, 29, 47, 3544, 144108, 576287, 576287, 144108, 3544, 47, 76, 11396, 1043060, 8205424, 15637256, 8205424, 1043060, 11396, 76
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Independent Edge Set
Eric Weisstein's World of Mathematics, Matching
Eric Weisstein's World of Mathematics, Torus Grid Graph
FORMULA
T(1, m) = A000032(m) for m<>2.
EXAMPLE
The start of the sequence as table:
* 1 2 4 7 11 18 ...
* 2 7 32 108 342 1104 ...
* 4 32 370 2764 19874 144108 ...
* 7 108 2764 41025 576287 8205424 ...
* 11 342 19874 576287 15637256 430996378 ...
* 18 1104 144108 8205424 430996378 23079663560 ...
* ...
CROSSREFS
Main diagonal is A270247. Row 2 is A102080.
Sequence in context: A210600 A220308 A203975 * A297889 A298294 A299388
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Mar 13 2016
STATUS
approved