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A183638
Number of (n+1) X 6 0..3 arrays with every 2 X 2 subblock summing to 6.
1
5684, 9256, 17612, 38056, 90524, 231736, 629132, 1793416, 5328764, 16413016, 52195052, 170891176, 574845404, 1983103096, 7003319372, 25265467336, 92897360444, 347253741976, 1316323506092, 5047850897896, 19540336713884
OFFSET
1,1
COMMENTS
Column 5 of A183642.
LINKS
FORMULA
Empirical: a(n) = 10*a(n-1) - 35*a(n-2) + 50*a(n-3) - 24*a(n-4).
Conjectures from Colin Barker, Mar 31 2018: (Start)
G.f.: 4*x*(1421 - 11896*x + 30998*x^2 - 24576*x^3) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)).
a(n) = 2702 + 301*2^(2+n) + 62*3^(1+n) + 4^(1+n).
(End)
EXAMPLE
Some solutions for 3 X 6:
2 0 1 2 3 0 2 1 2 3 1 1 1 1 1 1 1 1 2 3 3 3 1 0
1 3 2 1 0 3 1 2 1 0 2 2 3 1 3 1 3 1 1 0 0 0 2 3
1 1 0 3 2 1 2 1 2 3 1 1 0 2 0 2 0 2 2 3 3 3 1 0
CROSSREFS
Cf. A183642.
Sequence in context: A224690 A224683 A222824 * A192098 A287239 A204532
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 06 2011
STATUS
approved