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A235288 Number of (n+1)X(7+1) 0..3 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant stress 1X1 tilings) 1
836, 968, 1108, 1400, 1724, 2408, 3220, 4952, 7196, 12008, 18868, 33560, 56444, 105128, 186580, 358232, 660956, 1292648, 2448628, 4839320, 9327164, 18539048, 36139540, 72049112, 141513116, 282566888, 557838388, 1114758680, 2208549884 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A235289

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +3*a(n-2) -15*a(n-3) +4*a(n-4) +18*a(n-5) -12*a(n-6)

EXAMPLE

Some solutions for n=4

..3..2..3..2..3..2..3..2....1..3..0..3..0..3..0..3....3..1..3..1..3..0..3..0

..0..3..0..3..0..3..0..3....3..1..2..1..2..1..2..1....1..3..1..3..1..2..1..2

..1..0..1..0..1..0..1..0....1..3..0..3..0..3..0..3....3..1..3..1..3..0..3..0

..0..3..0..3..0..3..0..3....2..0..1..0..1..0..1..0....1..3..1..3..1..2..1..2

..3..2..3..2..3..2..3..2....1..3..0..3..0..3..0..3....3..1..3..1..3..0..3..0

CROSSREFS

Sequence in context: A236741 A113856 A245947 * A162945 A138850 A322524

Adjacent sequences:  A235285 A235286 A235287 * A235289 A235290 A235291

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 05 2014

STATUS

approved

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Last modified November 30 21:20 EST 2021. Contains 349426 sequences. (Running on oeis4.)