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A234489
Number of (n+1) X (7+1) 0..3 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 2 (constant-stress 1 X 1 tilings).
1
220334, 765738, 2659824, 9288710, 32545706, 114484712, 404043442, 1431125914, 5084793448, 18127421166, 64813774926, 232475602952, 836155485018, 3016451992646, 10910475434292, 39574863492918, 143905533079266
OFFSET
1,1
LINKS
EXAMPLE
Some solutions for n=1:
0 1 3 2 2 0 2 1 2 3 0 3 3 1 1 3 0 3 0 2 3 1 2 1
1 0 0 1 3 3 3 0 0 3 2 3 1 1 3 3 0 1 0 0 3 3 2 3
CROSSREFS
Column 7 of A234490.
Sequence in context: A257207 A204968 A294014 * A321160 A223369 A366824
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 26 2013
STATUS
approved