A253703 Number of (6+1) X (n+1) 0..1 arrays with every 2 X 2 subblock ne-sw antidiagonal difference unequal to its neighbors horizontally and nw+se diagonal sum unequal to its neighbors vertically.

1736, 1182, 1472, 1638, 2386, 3042, 4010, 5178, 6934, 8938, 12212, 16174, 22824, 30696, 43046, 57850, 79936, 107610, 148468, 201388, 277230, 375774, 516762, 699910, 965566, 1310400, 1809600, 2452546, 3377162, 4578316, 6298534, 8563704

Offset

1,1

Comments

Row 6 of A253698.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-2) +a(n-5) -a(n-6) +2*a(n-7) +a(n-8) -8*a(n-9) -a(n-10) +2*a(n-11) +5*a(n-13) -11*a(n-15) +6*a(n-17) +7*a(n-19) -4*a(n-21) for n>31.

Example

Some solutions for n=4
..1..0..1..1..0....0..1..1..0..0....1..1..0..0..1....1..1..0..1..0
..1..1..0..0..0....1..0..0..1..1....0..0..1..0..0....0..1..0..0..1
..0..0..1..0..0....0..1..0..1..1....1..0..0..1..1....0..0..1..1..0
..1..0..0..1..1....0..1..1..0..0....0..1..1..0..1....1..1..0..1..0
..0..1..1..0..1....1..0..0..1..0....1..0..1..0..1....1..1..0..0..1
..1..0..1..1..1....0..1..0..1..0....1..0..1..1..0....0..0..1..1..0
..0..0..1..0..1....0..1..0..0..1....1..1..0..0..1....0..0..1..1..0

Crossrefs

Cf. A253698.

Sequence in context: A280927 A095847 A253696 * A235014 A185766 A179160

Adjacent sequences: A253700 A253701 A253702 * A253704 A253705 A253706

Keyword

nonn

Author

R. H. Hardin, Jan 09 2015

Status

approved