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A234134
Number of (n+1) X (2+1) 0..3 arrays with every 2 X 2 subblock having the sum of the absolute values of all six edge and diagonal differences equal to 9.
1
80, 152, 296, 680, 1544, 4040, 9992, 28040, 72200, 209672, 549896, 1623560, 4294664, 12782600, 33951752, 101455880, 270016520, 808464392, 2153791496, 6455058440, 17205067784, 51589988360, 137539682312, 412518285320, 1099914412040
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) + 8*a(n-2) - 30*a(n-3) + 4*a(n-4) + 48*a(n-5) - 32*a(n-6).
Empirical g.f.: 8*x*(10 - 11*x - 100*x^2 + 122*x^3 + 172*x^4 - 200*x^5) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 8*x^2)). - Colin Barker, Oct 13 2018
EXAMPLE
Some solutions for n=5:
3 0 3 3 3 3 2 2 2 1 1 1 3 3 3 2 3 2 1 1 1
1 1 1 0 3 0 3 0 3 0 3 0 3 0 3 2 0 2 3 0 3
3 0 3 1 1 1 0 0 0 3 3 3 3 3 3 2 3 2 0 0 0
0 0 0 0 3 0 0 3 0 0 3 0 3 0 3 0 2 0 3 0 3
0 3 0 3 3 3 3 3 3 2 2 2 3 3 3 3 2 3 3 3 3
1 1 1 0 3 0 0 3 0 0 3 0 0 3 0 2 0 2 0 3 0
CROSSREFS
Column 2 of A234140.
Sequence in context: A202440 A248432 A107931 * A134769 A376909 A371150
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 19 2013
STATUS
approved