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A253699 Number of (2+1)X(n+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, 150, 282, 540, 1026, 1984, 3782, 7270, 13880, 26644, 51026, 97726, 187364, 358554, 687792, 1316136, 2524044, 4831726, 9262042, 17738282, 33988728, 65116062, 124738388, 239016216, 457824900, 877280898, 1680426234, 3219854846 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 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-4) +5*a(n-5) -7*a(n-6) -3*a(n-7) +9*a(n-8) -5*a(n-9) +a(n-10) +5*a(n-11) -6*a(n-12) -2*a(n-13) +4*a(n-14) -a(n-16)

EXAMPLE

Some solutions for n=4

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

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

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

CROSSREFS

Sequence in context: A044106 A044487 A253692 * A037975 A317095 A039468

Adjacent sequences:  A253696 A253697 A253698 * A253700 A253701 A253702

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 09 2015

STATUS

approved

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Last modified August 2 08:47 EDT 2021. Contains 346422 sequences. (Running on oeis4.)