A145801 - OEIS

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A145801

Number of islands of ones fitting in an n X n array with all ones connected only either two adjacent vertically or two adjacent horizontally.

%I #3 Mar 31 2012 12:35:08

%S 0,1,2,4,6,9,12,16,19,25,29,36

%N Number of islands of ones fitting in an n X n array with all ones connected only either two adjacent vertically or two adjacent horizontally.

%e 8 X 8 example with 16 islands

%e .0.1.0.1.0.1.0.1

%e .1.0.1.0.1.0.1.0

%e .0.1.0.1.0.1.0.1

%e .1.0.1.0.1.0.0.0

%e .1.0.1.0.1.0.1.1

%K nonn

%O 1,3

%A _R. H. Hardin_, Oct 19 2008