

A226918


Minimal number of 1X3 Itrominoes needed to prevent any further Itrominoe from being placed on an n X n grid.


2



0, 0, 3, 4, 5, 7, 9, 13, 16, 20, 24, 28
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OFFSET

1,3


COMMENTS

The Itrominoes must line up with the squares on the grid and must occupy exactly three squares (skew placements are not allowed).
a(n) is the independent domination number of a graph with one node per tromino and an edge for each pair of trominoes that conflict.  Rob Pratt, Oct 02 2019


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CROSSREFS



KEYWORD

nonn,more


AUTHOR



EXTENSIONS



STATUS

approved



