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A253467
Number of (n+1) X (6+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
1081504, 15888, 7784, 8272, 12680, 12800, 20864, 36352, 99200, 108800, 230144, 485632, 1483520, 1644800, 3578624, 7674112, 23632640, 26220800, 57154304, 122689792, 378018560, 419436800, 914365184, 1962940672, 6048193280
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = a(n-2) + 16*a(n-4) - 16*a(n-6) for n>8.
Empirical g.f.: 8*x*(135188 + 1986*x - 134215*x^2 - 952*x^3 - 2162396*x^4 - 31210*x^5 + 2148463*x^6 + 18176*x^7) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)*(1 + 4*x^2)). - Colin Barker, Dec 15 2018
EXAMPLE
Some solutions for n=1.
..0..0..1..2..0..2..1....0..0..1..2..1..2..2....0..0..2..1..2..1..0
..1..0..2..1..1..1..0....2..0..1..1..0..2..2....0..0..2..0..2..2..2
CROSSREFS
Column 6 of A253468.
Sequence in context: A252038 A236449 A352110 * A340132 A340405 A258704
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 01 2015
STATUS
approved