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Search: a303335 -id:a303335
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Array read by antidiagonals: T(m,n) is the number of minimum dominating sets in the m X n king graph.
+10
8
1, 2, 2, 1, 4, 1, 4, 2, 2, 4, 3, 16, 1, 16, 3, 1, 12, 4, 4, 12, 1, 8, 4, 3, 256, 3, 4, 8, 4, 64, 1, 144, 144, 1, 64, 4, 1, 32, 8, 16, 79, 16, 8, 32, 1, 13, 8, 4, 4096, 9, 9, 4096, 4, 8, 13, 5, 208, 1, 1024, 1656, 1, 1656, 1024, 1, 208, 5, 1, 80, 13, 64, 408, 64, 64, 408, 64, 13, 80, 1
OFFSET
1,2
COMMENTS
The minimum size of a dominating set is the domination number which in the case of an m X n king graph is given by (ceiling(m/3) * ceiling(n/3)).
LINKS
Stephan Mertens, Table of n, a(n) for n = 1..946 (first 276 terms from Andrew Howroyd)
Stephan Mertens, Domination Polynomials of the Grid, the Cylinder, the Torus, and the King Graph, arXiv:2408.08053 [math.CO], Aug 2024.
Eric Weisstein's World of Mathematics, King Graph
Eric Weisstein's World of Mathematics, Minimum Dominating Set
FORMULA
T(n,m) = T(m,n).
T(3*m, 3*n) = 1; T(3*m+1, 3*n) = (m^2 + 5*m + 2)^n; T(3*m+2, 3*n) = (m+2)^n.
T(3*m-1, 3*n-1) = A350819(m, n).
EXAMPLE
Table begins:
============================================
m\n | 1 2 3 4 5 6 7 8
----+---------------------------------------
1 | 1 2 1 4 3 1 8 4 ...
2 | 2 4 2 16 12 4 64 32 ...
3 | 1 2 1 4 3 1 8 4 ...
4 | 4 16 4 256 144 16 4096 1024 ...
5 | 3 12 3 144 79 9 1656 408 ...
6 | 1 4 1 16 9 1 64 16 ...
7 | 8 64 8 4096 1656 64 243856 29744 ...
8 | 4 32 4 1024 408 16 29744 3600 ...
...
CROSSREFS
Rows 1..3 are A347633, A350816, A347633.
Main diagonal is A347554.
Cf. A075561, A218663 (dominating sets), A286849 (minimal dominating sets), A303335, A350818, A350819.
KEYWORD
nonn,look,tabl
AUTHOR
Andrew Howroyd, Jan 17 2022
STATUS
approved
Array read by antidiagonals: T(m,n) is the number of minimal total dominating sets in the m X n king graph.
+10
6
0, 1, 1, 2, 6, 2, 1, 10, 10, 1, 2, 15, 20, 15, 2, 4, 52, 52, 52, 52, 4, 3, 105, 179, 141, 179, 105, 3, 4, 175, 418, 801, 801, 418, 175, 4, 8, 481, 1167, 2950, 7770, 2950, 1167, 481, 8, 9, 1028, 3498, 9792, 34790, 34790, 9792, 3498, 1028, 9, 10, 2000, 9074, 47527, 184318, 204372, 184318, 47527, 9074, 2000, 10
OFFSET
1,4
LINKS
Eric Weisstein's World of Mathematics, King Graph
Eric Weisstein's World of Mathematics, Total Dominating Set
FORMULA
T(n,m) = T(m,n).
EXAMPLE
Array begins:
================================================================
m\n | 1 2 3 4 5 6 7 8
----+-----------------------------------------------------------
1 | 0 1 2 1 2 4 3 4 ...
2 | 1 6 10 15 52 105 175 481 ...
3 | 2 10 20 52 179 418 1167 3498 ...
4 | 1 15 52 141 801 2950 9792 47527 ...
5 | 2 52 179 801 7770 34790 184318 1305358 ...
6 | 4 105 418 2950 34790 204372 1593094 14720683 ...
7 | 3 175 1167 9792 184318 1593094 16260853 231301551 ...
8 | 4 481 3498 47527 1305358 14720683 231301551 4570906041 ...
...
CROSSREFS
Rows 1..4 are A302655, A332392, A332393, A332394.
Main diagonal is A332391.
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Feb 10 2020
STATUS
approved
Number of minimum total dominating sets in the n X n king graph.
+10
4
0, 6, 8, 35, 1, 8684, 208, 604, 1192, 276696, 1362, 2, 2986, 32, 38772, 28520, 441984, 1024, 5047188
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, King Graph
Eric Weisstein's World of Mathematics, Total Dominating Set
CROSSREFS
Main diagonal of A303335.
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, Apr 19 2018
EXTENSIONS
a(6)-a(19) from Andrew Howroyd, Apr 21 2018
STATUS
approved
Array read by antidiagonals: T(m,n) = total domination number of the m X n king graph.
+10
4
1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 3, 4, 3, 2, 2, 3, 4, 4, 4, 3, 4, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 4, 4, 4, 5, 4, 4, 4, 5, 6, 5, 4, 6, 6, 6, 6, 4, 5, 6, 6, 6, 5, 6, 7, 8, 7, 6, 5, 6, 6, 6, 6, 6, 6, 8, 8, 8, 8, 6, 6, 6, 6, 7, 6, 6, 8, 9, 8, 9, 8, 9, 8, 6, 6, 7
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, King Graph
Eric Weisstein's World of Mathematics, Total Dominating Set
EXAMPLE
Table begins:
=======================================================
m\n| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
---+---------------------------------------------------
1 | 1 2 2 2 3 4 4 4 5 6 6 6 7 8 8 8 ...
2 | 2 2 2 2 3 4 4 4 5 6 6 6 7 8 8 8 ...
3 | 2 2 2 2 3 4 4 4 5 6 6 6 7 8 8 8 ...
4 | 2 2 2 4 4 4 6 6 6 8 8 8 10 10 10 12 ...
5 | 3 3 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ...
6 | 4 4 4 4 6 8 8 8 10 12 12 12 14 16 16 16 ...
7 | 4 4 4 6 7 8 9 10 11 12 14 14 16 17 18 19 ...
8 | 4 4 4 6 8 8 10 12 12 14 16 16 18 20 20 22 ...
9 | 5 5 5 6 9 10 11 12 15 16 17 18 21 22 23 24 ...
...
CROSSREFS
Main diagonal is A302401.
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Apr 22 2018
STATUS
approved
Number of minimum total dominating sets in the 2 X n king graph.
+10
1
1, 6, 9, 4, 8, 89, 56, 16, 64, 780, 304, 64, 384, 5472, 1536, 256, 2048, 33920, 7424, 1024, 10240, 194304, 34816, 4096, 49152, 1053696, 159744, 16384, 229376, 5488640, 720896, 65536, 1048576, 27721728, 3211264, 262144, 4718592, 136642560, 14155776, 1048576
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, King Graph
Eric Weisstein's World of Mathematics, Total Dominating Set
Index entries for linear recurrences with constant coefficients, signature (0,0,0,12,0,0,0,-48,0,0,0,64).
FORMULA
a(n) = 12*a(n-4) - 48*a(n-8) + 64*a(n-12) for n > 13.
G.f.: x*(1 + 6*x + 9*x^2 + 4*x^3 - 4*x^4 + 17*x^5 - 52*x^6 - 32*x^7 + 16*x^8 + 64*x^10 + 64*x^11 - 64*x^12)/((1 - 2*x^2)^3*(1 + 2*x^2)^3).
a(4*k) = 4^k; a(4*k+1) = 2*k*4^k for k > 0; a(4*k+2) = (k + 1)*(41*k + 48)*4^k/8; a(4*k+3) = (5*k + 9)*4^k.
MATHEMATICA
LinearRecurrence[{0, 0, 0, 12, 0, 0, 0, -48, 0, 0, 0, 64}, {1, 6, 9, 4, 8, 89, 56, 16, 64, 780, 304, 64, 384}, 40] (* Michael De Vlieger, Jan 19 2022 *)
PROG
(PARI) Vec((1 + 6*x + 9*x^2 + 4*x^3 - 4*x^4 + 17*x^5 - 52*x^6 - 32*x^7 + 16*x^8 + 64*x^10 + 64*x^11 - 64*x^12)/((1 - 2*x^2)^3*(1 + 2*x^2)^3) + O(x^40))
(PARI) a(n)={my(k=n\4); 4^k*if(n%2, if(n%4==1, (k==0) + 2*k, 5*k + 9), if(n%4==0, 1, (k + 1)*(41*k + 48)/8))}
CROSSREFS
Row 2 of A303335.
Cf. A350816.
KEYWORD
nonn,easy
AUTHOR
Andrew Howroyd, Jan 17 2022
STATUS
approved

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