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A384116
Array read by antidiagonals: T(n,m) is the number of total dominating sets in the n X m rook graph K_n X K_m.
4
1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 4, 9, 4, 1, 1, 11, 39, 39, 11, 1, 1, 26, 183, 334, 183, 26, 1, 1, 57, 833, 3087, 3087, 833, 57, 1, 1, 120, 3629, 27472, 53731, 27472, 3629, 120, 1, 1, 247, 15291, 236127, 922515, 922515, 236127, 15291, 247, 1, 1, 502, 63051, 1975246, 15524639, 30844786, 15524639, 1975246, 63051, 502, 1
OFFSET
0,12
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..1325 (first 51 antidiagonals)
Eric Weisstein's World of Mathematics, Rook Graph.
Eric Weisstein's World of Mathematics, Total Dominating Set.
FORMULA
T(n,m) = B(n,m) - Sum_{i=1..m} (-1)^i*binomial(m,i)*B(m-i,n), where B(n,m) = Sum_{i=0..m} (-1)^i*binomial(n,i)*binomial(m,i)*i!*(2^(n-i)-1)^(m-i).
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 0 1 4 11 26 57 ...
2 | 1 1 9 39 183 833 3629 ...
3 | 1 4 39 334 3087 27472 236127 ...
4 | 1 11 183 3087 53731 922515 15524639 ...
5 | 1 26 833 27472 922515 30844786 1019569593 ...
6 | 1 57 3629 236127 15524639 1019569593 66544564805 ...
7 | 1 120 15291 1975246 256594143 33329148492 4314985562475 ...
...
PROG
(PARI)
B(n, m) = {sum(i=0, min(n, m), (-1)^i*binomial(n, i)*binomial(m, i)*i!*(2^(n-i)-1)^(m-i))}
T(n, m) = {B(n, m) - sum(i=1, m, (-1)^i*binomial(m, i)*B(m-i, n))}
CROSSREFS
Main diagonal is A303208.
Column 0 is A000012.
Column 1 is A000295(n), n > 0.
Column 2 is A287063(n), n > 1.
Sequence in context: A178143 A070435 A070516 * A143298 A177839 A013669
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, May 19 2025
STATUS
approved