login
A360846
Array read by antidiagonals: T(m,n) is the number of dominating induced trees in the grid graph P_m X P_n.
3
1, 3, 3, 4, 8, 4, 4, 17, 17, 4, 4, 32, 65, 32, 4, 4, 66, 222, 222, 66, 4, 4, 130, 766, 1280, 766, 130, 4, 4, 262, 2685, 7629, 7629, 2685, 262, 4, 4, 522, 9450, 46032, 78981, 46032, 9450, 522, 4, 4, 1046, 33158, 278419, 820308, 820308, 278419, 33158, 1046, 4
OFFSET
1,2
COMMENTS
A dominating induced tree in a graph is an acyclic connected induced subgraph whose vertices are a dominating set.
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..435 (first 29 antidiagonals)
Eric Weisstein's World of Mathematics, Grid Graph.
FORMULA
T(n,m) = T(m,n).
EXAMPLE
Table starts:
=======================================================
m\n| 1 2 3 4 5 6 7 ...
---+---------------------------------------------------
1 | 1 3 4 4 4 4 4 ...
2 | 3 8 17 32 66 130 262 ...
3 | 4 17 65 222 766 2685 9450 ...
4 | 4 32 222 1280 7629 46032 278419 ...
5 | 4 66 766 7629 78981 820308 8520021 ...
6 | 4 130 2685 46032 820308 14605388 259809527 ...
7 | 4 262 9450 278419 8520021 259809527 7904828158 ...
...
CROSSREFS
Main diagonal is A360847.
Rows 1..2 are A113311(n-1), A360848.
Cf. A291872 (connected dominating sets), A360202 (induced trees).
Sequence in context: A049927 A329216 A266616 * A340429 A147679 A339054
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Feb 23 2023
STATUS
approved