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A253466
Number of (n+1) X (5+1) 0..2 arrays with every 2 X 2 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally, vertically, diagonally and antidiagonally.
1
162016, 8536, 5000, 7496, 8000, 12680, 20000, 33416, 68000, 116360, 260000, 448136, 1028000, 1775240, 4100000, 7083656, 16388000, 28317320, 65540000, 113251976, 262148000, 452990600, 1048580000, 1811945096, 4194308000, 7247763080
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 5*a(n-2) - 4*a(n-4) for n>6.
Empirical g.f.: 8*x*(20252 + 1067*x - 100635*x^2 - 4398*x^3 + 78883*x^4 + 1168*x^5) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)). - Colin Barker, Dec 14 2018
EXAMPLE
Some solutions for n=4:
..0..2..1..1..1..1....1..0..2..1..1..0....0..1..2..0..2..1....2..0..2..0..1..2
..1..1..2..0..1..0....0..1..1..2..0..1....0..2..1..1..0..2....2..2..1..1..0..2
..0..2..1..1..0..2....1..0..2..1..1..0....1..1..2..0..1..1....2..1..2..0..1..1
..1..1..2..0..1..1....0..1..1..2..0..1....0..2..1..1..0..2....0..2..1..1..0..2
..0..2..0..2..0..2....1..0..2..0..2..0....2..2..1..1..0..0....1..1..1..0..0..0
CROSSREFS
Column 5 of A253468.
Sequence in context: A114669 A204306 A120409 * A225811 A244348 A083633
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 01 2015
STATUS
approved