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A145809
Number of islands of ones fitting in an n X n array with all ones connected only either three adjacent vertically or three adjacent horizontally.
0
0, 0, 2, 2, 4, 6, 8, 10, 14, 15, 20, 24
OFFSET
1,3
EXAMPLE
8 X 8 example with 10 islands
.0.1.1.1.0.1.1.1
.1.0.0.0.0.0.0.0
.1.0.0.0.0.1.1.1
.1.0.1.1.1.0.0.0
.0.0.0.0.0.1.1.1
.1.0.1.1.1.0.0.0
.1.0.0.0.0.1.1.1
.1.0.1.1.1.0.0.0
CROSSREFS
Sequence in context: A300576 A118303 A145817 * A309711 A116859 A179999
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 20 2008
STATUS
approved