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A183637
Number of (n+1) X 5 0..3 arrays with every 2 X 2 subblock summing to 6.
1
1576, 2884, 6136, 14644, 38056, 105604, 309016, 945364, 3004936, 9877924, 33458296, 116413684, 414874216, 1510107844, 5598165976, 21077667604, 80389277896, 309840123364, 1204303904056, 4712234595124, 18534372807976
OFFSET
1,1
COMMENTS
Column 4 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*(394 - 3219*x + 8114*x^2 - 6144*x^3) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)).
a(n) = 570 + 45*2^(3+n) + 10*3^(2+n) + 4^(1+n).
(End)
EXAMPLE
Some solutions for 3 X 5:
2 1 2 0 2 2 1 2 2 2 3 0 3 0 1 3 2 3 2 3
3 0 3 1 3 0 3 0 2 0 0 3 0 3 2 0 1 0 1 0
2 1 2 0 2 3 0 3 1 3 3 0 3 0 1 2 3 2 3 2
CROSSREFS
Cf. A183642.
Sequence in context: A203087 A278559 A263525 * A223399 A210294 A203961
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 06 2011
STATUS
approved