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A163037
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Number of nX2 binary arrays with all 1s connected and a path of 1s from left column to right column
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2
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1, 7, 28, 88, 245, 639, 1608, 3968, 9689, 23527, 56964, 137720, 332717, 803519, 1940176, 4684352, 11309425, 27303815, 65917740, 159140056, 384198693, 927538367, 2239276440, 5406092352, 13051462345, 31509018343, 76069500436
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OFFSET
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1,2
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COMMENTS
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Sum of the elements in the first n rows of the triangle defined in the comment in A034182: 1; 3,3; 7,7,7;... (if the empirical recurrence is correct). - J. M. Bergot, Mar 22 2013
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LINKS
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FORMULA
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Empirical: a(n)=5*a(n-1)-8*a(n-2)+4*a(n-3)+a(n-4)-a(n-5) = A001333(n+3)/2 -A097080(n+1)/2. G.f.: x*(1+x)^2/((x^2+2*x-1)*(x-1)^3). [From R. J. Mathar, Aug 11 2009]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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