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A235277
Number of (n+1) X (7+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant-stress 1 X 1 tilings).
1
6208, 8012, 10088, 14672, 20440, 33464, 51800, 93992, 160888, 317192, 593048, 1246472, 2502520, 5518664, 11691800, 26719112, 58853368, 138080072, 312608408, 747636872, 1725115000, 4182997064, 9778136600, 23940964232, 56457574648
OFFSET
1,1
COMMENTS
Column 7 of A235280.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +15*a(n-2) -15*a(n-3) -80*a(n-4) +80*a(n-5) +180*a(n-6) -180*a(n-7) -144*a(n-8) +144*a(n-9).
EXAMPLE
Some solutions for n=4:
0 3 0 4 0 3 0 4 0 4 0 2 0 2 0 2 1 4 0 3 1 3 1 3
2 0 2 1 2 0 2 1 3 2 3 0 3 0 3 0 3 1 2 0 3 0 3 0
0 3 0 4 0 3 0 4 0 4 0 2 0 2 0 2 1 4 0 3 1 3 1 3
2 0 2 1 2 0 2 1 4 3 4 1 4 1 4 1 3 1 2 0 3 0 3 0
0 3 0 4 0 3 0 4 0 4 0 2 0 2 0 2 1 4 0 3 1 3 1 3
CROSSREFS
Sequence in context: A186602 A031836 A094494 * A246889 A172629 A172697
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 05 2014
STATUS
approved