A163037 Number of nX2 binary arrays with all 1s connected and a path of 1s from left column to right column

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

Offset

1,2

Comments

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

Links

R. H. Hardin, Table of n, a(n) for n=1..100

Formula

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]

Crossrefs

Sequence in context: A369806 A156928 A117473 * A224153 A361771 A276236

Adjacent sequences: A163034 A163035 A163036 * A163038 A163039 A163040

Keyword

nonn

Author

R. H. Hardin Jul 20 2009

Status

approved