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A253692 Number of (n+1)X(2+1) 0..1 arrays with every 2X2 subblock ne-sw antidiagonal difference unequal to its neighbors horizontally and nw+se diagonal sum unequal to its neighbors vertically 1
40, 76, 146, 304, 602, 1182, 2416, 4772, 9652, 19152, 38524, 76996, 154072, 308634, 617062, 1236382, 2472602, 4951496, 9907740, 19832536, 39695188, 79445558, 159023072, 318264564, 637042828, 1275004742, 2551980574, 5107782140 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A253698

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-2) +2*a(n-3) -2*a(n-4) -a(n-5) -7*a(n-6) -3*a(n-7) +9*a(n-8) +3*a(n-9) +a(n-10) -a(n-11) -6*a(n-12) +4*a(n-14) -a(n-16)

EXAMPLE

Some solutions for n=4

..1..0..1....1..1..1....0..0..1....1..1..0....0..1..0....0..0..1....0..0..1

..1..1..0....0..1..1....1..0..1....0..1..0....0..1..1....1..1..0....0..0..0

..0..0..1....1..0..0....1..1..0....0..0..1....1..0..0....1..1..0....0..1..1

..1..0..0....0..1..0....0..0..1....1..1..0....0..1..0....0..0..1....1..0..1

..0..1..1....0..0..0....1..0..0....0..1..0....1..1..0....1..0..0....1..0..1

CROSSREFS

Sequence in context: A260537 A044106 A044487 * A253699 A037975 A317095

Adjacent sequences:  A253689 A253690 A253691 * A253693 A253694 A253695

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 09 2015

STATUS

approved

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Last modified August 2 09:22 EDT 2021. Contains 346422 sequences. (Running on oeis4.)