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A203376
Number of (n+1)X7 0..1 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements
1
2916, 70996, 1764360, 44183028, 1109832180, 27913330472, 702420750924, 17679917387404, 445045123432096, 11203277447970636, 282028756620227124, 7099777698513424920, 178729975670304808348, 4499358353656818662428
OFFSET
1,1
COMMENTS
Column 6 of A203378
LINKS
FORMULA
Empirical: a(n) = 55*a(n-1) -1109*a(n-2) +11330*a(n-3) -67206*a(n-4) +247404*a(n-5) -582440*a(n-6) +881876*a(n-7) -846764*a(n-8) +499200*a(n-9) -172400*a(n-10) +33152*a(n-11) -3264*a(n-12) +128*a(n-13)
EXAMPLE
Some solutions for n=4
..0..1..1..0..1..1..0....0..1..1..1..1..1..1....1..1..1..0..1..1..0
..0..0..1..1..0..1..1....1..0..1..1..0..1..1....1..1..0..1..1..0..0
..1..0..0..1..1..1..0....1..1..1..1..1..0..1....1..1..1..1..0..0..1
..0..0..1..0..1..1..1....0..1..0..1..0..1..0....0..1..1..0..0..1..1
..1..0..0..0..0..1..0....1..0..0..0..1..0..1....1..0..1..1..0..0..1
CROSSREFS
Sequence in context: A250953 A334002 A344474 * A183360 A209046 A209018
KEYWORD
nonn
AUTHOR
R. H. Hardin Dec 31 2011
STATUS
approved