login
A207450
Number of n X 5 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 1 vertically.
1
16, 256, 1008, 2560, 5200, 9216, 14896, 22528, 32400, 44800, 60016, 78336, 100048, 125440, 154800, 188416, 226576, 269568, 317680, 371200, 430416, 495616, 567088, 645120, 730000, 822016, 921456, 1028608, 1143760, 1267200, 1399216, 1540096
OFFSET
1,1
COMMENTS
Column 5 of A207453.
LINKS
FORMULA
Empirical: a(n) = 48*n^3 - 32*n^2.
Conjectures from Colin Barker, Jun 23 2018: (Start)
G.f.: 16*x*(1 + 12*x + 5*x^2) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>4.
(End).
EXAMPLE
Some solutions for n=5:
0 1 1 1 0 1 1 0 1 0 0 1 1 0 1 0 1 1 0 0
1 0 1 0 1 0 1 1 0 1 1 1 0 1 1 0 1 0 1 1
1 0 1 0 0 0 1 1 0 0 1 1 0 1 1 0 1 0 1 0
1 0 1 0 0 0 1 1 0 0 1 1 0 1 1 0 1 0 1 0
1 0 1 0 0 0 1 1 0 0 0 1 0 1 1 0 1 0 1 0
CROSSREFS
Cf. A207453.
Sequence in context: A207771 A207898 A207658 * A208552 A267717 A223190
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 17 2012
STATUS
approved